feat: Initial commit

utils/config.py

@@ -0,0 +1,696 @@
+"""
+The code is base on https://github.com/Pointcept/Pointcept
+"""
+import ast
+import copy
+import os
+import os.path as osp
+import platform
+import shutil
+import sys
+import tempfile
+import uuid
+import warnings
+from argparse import Action, ArgumentParser
+from collections import abc
+from importlib import import_module
+
+from addict import Dict
+from yapf.yapflib.yapf_api import FormatCode
+
+from .misc import import_modules_from_strings
+from .path import check_file_exist
+
+if platform.system() == "Windows":
+    import regex as re
+else:
+    import re
+
+BASE_KEY = "_base_"
+DELETE_KEY = "_delete_"
+DEPRECATION_KEY = "_deprecation_"
+RESERVED_KEYS = ["filename", "text", "pretty_text"]
+
+
+class ConfigDict(Dict):
+    def __missing__(self, name):
+        raise KeyError(name)
+
+    def __getattr__(self, name):
+        try:
+            value = super(ConfigDict, self).__getattr__(name)
+        except KeyError:
+            ex = AttributeError(
+                f"'{self.__class__.__name__}' object has no " f"attribute '{name}'"
+            )
+        except Exception as e:
+            ex = e
+        else:
+            return value
+        raise ex
+
+
+def add_args(parser, cfg, prefix=""):
+    for k, v in cfg.items():
+        if isinstance(v, str):
+            parser.add_argument("--" + prefix + k)
+        elif isinstance(v, int):
+            parser.add_argument("--" + prefix + k, type=int)
+        elif isinstance(v, float):
+            parser.add_argument("--" + prefix + k, type=float)
+        elif isinstance(v, bool):
+            parser.add_argument("--" + prefix + k, action="store_true")
+        elif isinstance(v, dict):
+            add_args(parser, v, prefix + k + ".")
+        elif isinstance(v, abc.Iterable):
+            parser.add_argument("--" + prefix + k, type=type(v[0]), nargs="+")
+        else:
+            print(f"cannot parse key {prefix + k} of type {type(v)}")
+    return parser
+
+
+class Config:
+    """A facility for config and config files.
+
+    It supports common file formats as configs: python/json/yaml. The interface
+    is the same as a dict object and also allows access config values as
+    attributes.
+
+    Example:
+        >>> cfg = Config(dict(a=1, b=dict(b1=[0, 1])))
+        >>> cfg.a
+        1
+        >>> cfg.b
+        {'b1': [0, 1]}
+        >>> cfg.b.b1
+        [0, 1]
+        >>> cfg = Config.fromfile('tests/data/config/a.py')
+        >>> cfg.filename
+        "/home/kchen/projects/mmcv/tests/data/config/a.py"
+        >>> cfg.item4
+        'test'
+        >>> cfg
+        "Config [path: /home/kchen/projects/mmcv/tests/data/config/a.py]: "
+        "{'item1': [1, 2], 'item2': {'a': 0}, 'item3': True, 'item4': 'test'}"
+    """
+
+    @staticmethod
+    def _validate_py_syntax(filename):
+        with open(filename, "r", encoding="utf-8") as f:
+            # Setting encoding explicitly to resolve coding issue on windows
+            content = f.read()
+        try:
+            ast.parse(content)
+        except SyntaxError as e:
+            raise SyntaxError(
+                "There are syntax errors in config " f"file {filename}: {e}"
+            )
+
+    @staticmethod
+    def _substitute_predefined_vars(filename, temp_config_name):
+        file_dirname = osp.dirname(filename)
+        file_basename = osp.basename(filename)
+        file_basename_no_extension = osp.splitext(file_basename)[0]
+        file_extname = osp.splitext(filename)[1]
+        support_templates = dict(
+            fileDirname=file_dirname,
+            fileBasename=file_basename,
+            fileBasenameNoExtension=file_basename_no_extension,
+            fileExtname=file_extname,
+        )
+        with open(filename, "r", encoding="utf-8") as f:
+            # Setting encoding explicitly to resolve coding issue on windows
+            config_file = f.read()
+        for key, value in support_templates.items():
+            regexp = r"\{\{\s*" + str(key) + r"\s*\}\}"
+            value = value.replace("\\", "/")
+            config_file = re.sub(regexp, value, config_file)
+        with open(temp_config_name, "w", encoding="utf-8") as tmp_config_file:
+            tmp_config_file.write(config_file)
+
+    @staticmethod
+    def _pre_substitute_base_vars(filename, temp_config_name):
+        """Substitute base variable placehoders to string, so that parsing
+        would work."""
+        with open(filename, "r", encoding="utf-8") as f:
+            # Setting encoding explicitly to resolve coding issue on windows
+            config_file = f.read()
+        base_var_dict = {}
+        regexp = r"\{\{\s*" + BASE_KEY + r"\.([\w\.]+)\s*\}\}"
+        base_vars = set(re.findall(regexp, config_file))
+        for base_var in base_vars:
+            randstr = f"_{base_var}_{uuid.uuid4().hex.lower()[:6]}"
+            base_var_dict[randstr] = base_var
+            regexp = r"\{\{\s*" + BASE_KEY + r"\." + base_var + r"\s*\}\}"
+            config_file = re.sub(regexp, f'"{randstr}"', config_file)
+        with open(temp_config_name, "w", encoding="utf-8") as tmp_config_file:
+            tmp_config_file.write(config_file)
+        return base_var_dict
+
+    @staticmethod
+    def _substitute_base_vars(cfg, base_var_dict, base_cfg):
+        """Substitute variable strings to their actual values."""
+        cfg = copy.deepcopy(cfg)
+
+        if isinstance(cfg, dict):
+            for k, v in cfg.items():
+                if isinstance(v, str) and v in base_var_dict:
+                    new_v = base_cfg
+                    for new_k in base_var_dict[v].split("."):
+                        new_v = new_v[new_k]
+                    cfg[k] = new_v
+                elif isinstance(v, (list, tuple, dict)):
+                    cfg[k] = Config._substitute_base_vars(v, base_var_dict, base_cfg)
+        elif isinstance(cfg, tuple):
+            cfg = tuple(
+                Config._substitute_base_vars(c, base_var_dict, base_cfg) for c in cfg
+            )
+        elif isinstance(cfg, list):
+            cfg = [
+                Config._substitute_base_vars(c, base_var_dict, base_cfg) for c in cfg
+            ]
+        elif isinstance(cfg, str) and cfg in base_var_dict:
+            new_v = base_cfg
+            for new_k in base_var_dict[cfg].split("."):
+                new_v = new_v[new_k]
+            cfg = new_v
+
+        return cfg
+
+    @staticmethod
+    def _file2dict(filename, use_predefined_variables=True):
+        filename = osp.abspath(osp.expanduser(filename))
+        check_file_exist(filename)
+        fileExtname = osp.splitext(filename)[1]
+        if fileExtname not in [".py", ".json", ".yaml", ".yml"]:
+            raise IOError("Only py/yml/yaml/json type are supported now!")
+
+        with tempfile.TemporaryDirectory() as temp_config_dir:
+            temp_config_file = tempfile.NamedTemporaryFile(
+                dir=temp_config_dir, suffix=fileExtname
+            )
+            if platform.system() == "Windows":
+                temp_config_file.close()
+            temp_config_name = osp.basename(temp_config_file.name)
+            # Substitute predefined variables
+            if use_predefined_variables:
+                Config._substitute_predefined_vars(filename, temp_config_file.name)
+            else:
+                shutil.copyfile(filename, temp_config_file.name)
+            # Substitute base variables from placeholders to strings
+            base_var_dict = Config._pre_substitute_base_vars(
+                temp_config_file.name, temp_config_file.name
+            )
+
+            if filename.endswith(".py"):
+                temp_module_name = osp.splitext(temp_config_name)[0]
+                sys.path.insert(0, temp_config_dir)
+                Config._validate_py_syntax(filename)
+                mod = import_module(temp_module_name)
+                sys.path.pop(0)
+                cfg_dict = {
+                    name: value
+                    for name, value in mod.__dict__.items()
+                    if not name.startswith("__")
+                }
+                # delete imported module
+                del sys.modules[temp_module_name]
+            elif filename.endswith((".yml", ".yaml", ".json")):
+                raise NotImplementedError
+            # close temp file
+            temp_config_file.close()
+
+        # check deprecation information
+        if DEPRECATION_KEY in cfg_dict:
+            deprecation_info = cfg_dict.pop(DEPRECATION_KEY)
+            warning_msg = (
+                f"The config file {filename} will be deprecated " "in the future."
+            )
+            if "expected" in deprecation_info:
+                warning_msg += f' Please use {deprecation_info["expected"]} ' "instead."
+            if "reference" in deprecation_info:
+                warning_msg += (
+                    " More information can be found at "
+                    f'{deprecation_info["reference"]}'
+                )
+            warnings.warn(warning_msg)
+
+        cfg_text = filename + "\n"
+        with open(filename, "r", encoding="utf-8") as f:
+            # Setting encoding explicitly to resolve coding issue on windows
+            cfg_text += f.read()
+
+        if BASE_KEY in cfg_dict:
+            cfg_dir = osp.dirname(filename)
+            base_filename = cfg_dict.pop(BASE_KEY)
+            base_filename = (
+                base_filename if isinstance(base_filename, list) else [base_filename]
+            )
+
+            cfg_dict_list = list()
+            cfg_text_list = list()
+            for f in base_filename:
+                _cfg_dict, _cfg_text = Config._file2dict(osp.join(cfg_dir, f))
+                cfg_dict_list.append(_cfg_dict)
+                cfg_text_list.append(_cfg_text)
+
+            base_cfg_dict = dict()
+            for c in cfg_dict_list:
+                duplicate_keys = base_cfg_dict.keys() & c.keys()
+                if len(duplicate_keys) > 0:
+                    raise KeyError(
+                        "Duplicate key is not allowed among bases. "
+                        f"Duplicate keys: {duplicate_keys}"
+                    )
+                base_cfg_dict.update(c)
+
+            # Substitute base variables from strings to their actual values
+            cfg_dict = Config._substitute_base_vars(
+                cfg_dict, base_var_dict, base_cfg_dict
+            )
+
+            base_cfg_dict = Config._merge_a_into_b(cfg_dict, base_cfg_dict)
+            cfg_dict = base_cfg_dict
+
+            # merge cfg_text
+            cfg_text_list.append(cfg_text)
+            cfg_text = "\n".join(cfg_text_list)
+
+        return cfg_dict, cfg_text
+
+    @staticmethod
+    def _merge_a_into_b(a, b, allow_list_keys=False):
+        """merge dict ``a`` into dict ``b`` (non-inplace).
+
+        Values in ``a`` will overwrite ``b``. ``b`` is copied first to avoid
+        in-place modifications.
+
+        Args:
+            a (dict): The source dict to be merged into ``b``.
+            b (dict): The origin dict to be fetch keys from ``a``.
+            allow_list_keys (bool): If True, int string keys (e.g. '0', '1')
+              are allowed in source ``a`` and will replace the element of the
+              corresponding index in b if b is a list. Default: False.
+
+        Returns:
+            dict: The modified dict of ``b`` using ``a``.
+
+        Examples:
+            # Normally merge a into b.
+            >>> Config._merge_a_into_b(
+            ...     dict(obj=dict(a=2)), dict(obj=dict(a=1)))
+            {'obj': {'a': 2}}
+
+            # Delete b first and merge a into b.
+            >>> Config._merge_a_into_b(
+            ...     dict(obj=dict(_delete_=True, a=2)), dict(obj=dict(a=1)))
+            {'obj': {'a': 2}}
+
+            # b is a list
+            >>> Config._merge_a_into_b(
+            ...     {'0': dict(a=2)}, [dict(a=1), dict(b=2)], True)
+            [{'a': 2}, {'b': 2}]
+        """
+        b = b.copy()
+        for k, v in a.items():
+            if allow_list_keys and k.isdigit() and isinstance(b, list):
+                k = int(k)
+                if len(b) <= k:
+                    raise KeyError(f"Index {k} exceeds the length of list {b}")
+                b[k] = Config._merge_a_into_b(v, b[k], allow_list_keys)
+            elif isinstance(v, dict) and k in b and not v.pop(DELETE_KEY, False):
+                allowed_types = (dict, list) if allow_list_keys else dict
+                if not isinstance(b[k], allowed_types):
+                    raise TypeError(
+                        f"{k}={v} in child config cannot inherit from base "
+                        f"because {k} is a dict in the child config but is of "
+                        f"type {type(b[k])} in base config. You may set "
+                        f"`{DELETE_KEY}=True` to ignore the base config"
+                    )
+                b[k] = Config._merge_a_into_b(v, b[k], allow_list_keys)
+            else:
+                b[k] = v
+        return b
+
+    @staticmethod
+    def fromfile(filename, use_predefined_variables=True, import_custom_modules=True):
+        cfg_dict, cfg_text = Config._file2dict(filename, use_predefined_variables)
+        if import_custom_modules and cfg_dict.get("custom_imports", None):
+            import_modules_from_strings(**cfg_dict["custom_imports"])
+        return Config(cfg_dict, cfg_text=cfg_text, filename=filename)
+
+    @staticmethod
+    def fromstring(cfg_str, file_format):
+        """Generate config from config str.
+
+        Args:
+            cfg_str (str): Config str.
+            file_format (str): Config file format corresponding to the
+               config str. Only py/yml/yaml/json type are supported now!
+
+        Returns:
+            obj:`Config`: Config obj.
+        """
+        if file_format not in [".py", ".json", ".yaml", ".yml"]:
+            raise IOError("Only py/yml/yaml/json type are supported now!")
+        if file_format != ".py" and "dict(" in cfg_str:
+            # check if users specify a wrong suffix for python
+            warnings.warn('Please check "file_format", the file format may be .py')
+        with tempfile.NamedTemporaryFile(
+            "w", encoding="utf-8", suffix=file_format, delete=False
+        ) as temp_file:
+            temp_file.write(cfg_str)
+            # on windows, previous implementation cause error
+            # see PR 1077 for details
+        cfg = Config.fromfile(temp_file.name)
+        os.remove(temp_file.name)
+        return cfg
+
+    @staticmethod
+    def auto_argparser(description=None):
+        """Generate argparser from config file automatically (experimental)"""
+        partial_parser = ArgumentParser(description=description)
+        partial_parser.add_argument("config", help="config file path")
+        cfg_file = partial_parser.parse_known_args()[0].config
+        cfg = Config.fromfile(cfg_file)
+        parser = ArgumentParser(description=description)
+        parser.add_argument("config", help="config file path")
+        add_args(parser, cfg)
+        return parser, cfg
+
+    def __init__(self, cfg_dict=None, cfg_text=None, filename=None):
+        if cfg_dict is None:
+            cfg_dict = dict()
+        elif not isinstance(cfg_dict, dict):
+            raise TypeError("cfg_dict must be a dict, but " f"got {type(cfg_dict)}")
+        for key in cfg_dict:
+            if key in RESERVED_KEYS:
+                raise KeyError(f"{key} is reserved for config file")
+
+        super(Config, self).__setattr__("_cfg_dict", ConfigDict(cfg_dict))
+        super(Config, self).__setattr__("_filename", filename)
+        if cfg_text:
+            text = cfg_text
+        elif filename:
+            with open(filename, "r") as f:
+                text = f.read()
+        else:
+            text = ""
+        super(Config, self).__setattr__("_text", text)
+
+    @property
+    def filename(self):
+        return self._filename
+
+    @property
+    def text(self):
+        return self._text
+
+    @property
+    def pretty_text(self):
+        indent = 4
+
+        def _indent(s_, num_spaces):
+            s = s_.split("\n")
+            if len(s) == 1:
+                return s_
+            first = s.pop(0)
+            s = [(num_spaces * " ") + line for line in s]
+            s = "\n".join(s)
+            s = first + "\n" + s
+            return s
+
+        def _format_basic_types(k, v, use_mapping=False):
+            if isinstance(v, str):
+                v_str = f"'{v}'"
+            else:
+                v_str = str(v)
+
+            if use_mapping:
+                k_str = f"'{k}'" if isinstance(k, str) else str(k)
+                attr_str = f"{k_str}: {v_str}"
+            else:
+                attr_str = f"{str(k)}={v_str}"
+            attr_str = _indent(attr_str, indent)
+
+            return attr_str
+
+        def _format_list(k, v, use_mapping=False):
+            # check if all items in the list are dict
+            if all(isinstance(_, dict) for _ in v):
+                v_str = "[\n"
+                v_str += "\n".join(
+                    f"dict({_indent(_format_dict(v_), indent)})," for v_ in v
+                ).rstrip(",")
+                if use_mapping:
+                    k_str = f"'{k}'" if isinstance(k, str) else str(k)
+                    attr_str = f"{k_str}: {v_str}"
+                else:
+                    attr_str = f"{str(k)}={v_str}"
+                attr_str = _indent(attr_str, indent) + "]"
+            else:
+                attr_str = _format_basic_types(k, v, use_mapping)
+            return attr_str
+
+        def _contain_invalid_identifier(dict_str):
+            contain_invalid_identifier = False
+            for key_name in dict_str:
+                contain_invalid_identifier |= not str(key_name).isidentifier()
+            return contain_invalid_identifier
+
+        def _format_dict(input_dict, outest_level=False):
+            r = ""
+            s = []
+
+            use_mapping = _contain_invalid_identifier(input_dict)
+            if use_mapping:
+                r += "{"
+            for idx, (k, v) in enumerate(input_dict.items()):
+                is_last = idx >= len(input_dict) - 1
+                end = "" if outest_level or is_last else ","
+                if isinstance(v, dict):
+                    v_str = "\n" + _format_dict(v)
+                    if use_mapping:
+                        k_str = f"'{k}'" if isinstance(k, str) else str(k)
+                        attr_str = f"{k_str}: dict({v_str}"
+                    else:
+                        attr_str = f"{str(k)}=dict({v_str}"
+                    attr_str = _indent(attr_str, indent) + ")" + end
+                elif isinstance(v, list):
+                    attr_str = _format_list(k, v, use_mapping) + end
+                else:
+                    attr_str = _format_basic_types(k, v, use_mapping) + end
+
+                s.append(attr_str)
+            r += "\n".join(s)
+            if use_mapping:
+                r += "}"
+            return r
+
+        cfg_dict = self._cfg_dict.to_dict()
+        text = _format_dict(cfg_dict, outest_level=True)
+        # copied from setup.cfg
+        yapf_style = dict(
+            based_on_style="pep8",
+            blank_line_before_nested_class_or_def=True,
+            split_before_expression_after_opening_paren=True,
+        )
+        text, _ = FormatCode(text, style_config=yapf_style, verify=True)
+
+        return text
+
+    def __repr__(self):
+        return f"Config (path: {self.filename}): {self._cfg_dict.__repr__()}"
+
+    def __len__(self):
+        return len(self._cfg_dict)
+
+    def __getattr__(self, name):
+        return getattr(self._cfg_dict, name)
+
+    def __getitem__(self, name):
+        return self._cfg_dict.__getitem__(name)
+
+    def __setattr__(self, name, value):
+        if isinstance(value, dict):
+            value = ConfigDict(value)
+        self._cfg_dict.__setattr__(name, value)
+
+    def __setitem__(self, name, value):
+        if isinstance(value, dict):
+            value = ConfigDict(value)
+        self._cfg_dict.__setitem__(name, value)
+
+    def __iter__(self):
+        return iter(self._cfg_dict)
+
+    def __getstate__(self):
+        return (self._cfg_dict, self._filename, self._text)
+
+    def __setstate__(self, state):
+        _cfg_dict, _filename, _text = state
+        super(Config, self).__setattr__("_cfg_dict", _cfg_dict)
+        super(Config, self).__setattr__("_filename", _filename)
+        super(Config, self).__setattr__("_text", _text)
+
+    def dump(self, file=None):
+        cfg_dict = super(Config, self).__getattribute__("_cfg_dict").to_dict()
+        if self.filename.endswith(".py"):
+            if file is None:
+                return self.pretty_text
+            else:
+                with open(file, "w", encoding="utf-8") as f:
+                    f.write(self.pretty_text)
+        else:
+            import mmcv
+
+            if file is None:
+                file_format = self.filename.split(".")[-1]
+                return mmcv.dump(cfg_dict, file_format=file_format)
+            else:
+                mmcv.dump(cfg_dict, file)
+
+    def merge_from_dict(self, options, allow_list_keys=True):
+        """Merge list into cfg_dict.
+
+        Merge the dict parsed by MultipleKVAction into this cfg.
+
+        Examples:
+            >>> options = {'models.backbone.depth': 50,
+            ...            'models.backbone.with_cp':True}
+            >>> cfg = Config(dict(models=dict(backbone=dict(type='ResNet'))))
+            >>> cfg.merge_from_dict(options)
+            >>> cfg_dict = super(Config, self).__getattribute__('_cfg_dict')
+            >>> assert cfg_dict == dict(
+            ...     models=dict(backbone=dict(depth=50, with_cp=True)))
+
+            # Merge list element
+            >>> cfg = Config(dict(pipeline=[
+            ...     dict(type='LoadImage'), dict(type='LoadAnnotations')]))
+            >>> options = dict(pipeline={'0': dict(type='SelfLoadImage')})
+            >>> cfg.merge_from_dict(options, allow_list_keys=True)
+            >>> cfg_dict = super(Config, self).__getattribute__('_cfg_dict')
+            >>> assert cfg_dict == dict(pipeline=[
+            ...     dict(type='SelfLoadImage'), dict(type='LoadAnnotations')])
+
+        Args:
+            options (dict): dict of configs to merge from.
+            allow_list_keys (bool): If True, int string keys (e.g. '0', '1')
+              are allowed in ``options`` and will replace the element of the
+              corresponding index in the config if the config is a list.
+              Default: True.
+        """
+        option_cfg_dict = {}
+        for full_key, v in options.items():
+            d = option_cfg_dict
+            key_list = full_key.split(".")
+            for subkey in key_list[:-1]:
+                d.setdefault(subkey, ConfigDict())
+                d = d[subkey]
+            subkey = key_list[-1]
+            d[subkey] = v
+
+        cfg_dict = super(Config, self).__getattribute__("_cfg_dict")
+        super(Config, self).__setattr__(
+            "_cfg_dict",
+            Config._merge_a_into_b(
+                option_cfg_dict, cfg_dict, allow_list_keys=allow_list_keys
+            ),
+        )
+
+
+class DictAction(Action):
+    """
+    argparse action to split an argument into KEY=VALUE form
+    on the first = and append to a dictionary. List options can
+    be passed as comma separated values, i.e 'KEY=V1,V2,V3', or with explicit
+    brackets, i.e. 'KEY=[V1,V2,V3]'. It also support nested brackets to build
+    list/tuple values. e.g. 'KEY=[(V1,V2),(V3,V4)]'
+    """
+
+    @staticmethod
+    def _parse_int_float_bool(val):
+        try:
+            return int(val)
+        except ValueError:
+            pass
+        try:
+            return float(val)
+        except ValueError:
+            pass
+        if val.lower() in ["true", "false"]:
+            return True if val.lower() == "true" else False
+        return val
+
+    @staticmethod
+    def _parse_iterable(val):
+        """Parse iterable values in the string.
+
+        All elements inside '()' or '[]' are treated as iterable values.
+
+        Args:
+            val (str): Value string.
+
+        Returns:
+            list | tuple: The expanded list or tuple from the string.
+
+        Examples:
+            >>> DictAction._parse_iterable('1,2,3')
+            [1, 2, 3]
+            >>> DictAction._parse_iterable('[a, b, c]')
+            ['a', 'b', 'c']
+            >>> DictAction._parse_iterable('[(1, 2, 3), [a, b], c]')
+            [(1, 2, 3), ['a', 'b'], 'c']
+        """
+
+        def find_next_comma(string):
+            """Find the position of next comma in the string.
+
+            If no ',' is found in the string, return the string length. All
+            chars inside '()' and '[]' are treated as one element and thus ','
+            inside these brackets are ignored.
+            """
+            assert (string.count("(") == string.count(")")) and (
+                string.count("[") == string.count("]")
+            ), f"Imbalanced brackets exist in {string}"
+            end = len(string)
+            for idx, char in enumerate(string):
+                pre = string[:idx]
+                # The string before this ',' is balanced
+                if (
+                    (char == ",")
+                    and (pre.count("(") == pre.count(")"))
+                    and (pre.count("[") == pre.count("]"))
+                ):
+                    end = idx
+                    break
+            return end
+
+        # Strip ' and " characters and replace whitespace.
+        val = val.strip("'\"").replace(" ", "")
+        is_tuple = False
+        if val.startswith("(") and val.endswith(")"):
+            is_tuple = True
+            val = val[1:-1]
+        elif val.startswith("[") and val.endswith("]"):
+            val = val[1:-1]
+        elif "," not in val:
+            # val is a single value
+            return DictAction._parse_int_float_bool(val)
+
+        values = []
+        while len(val) > 0:
+            comma_idx = find_next_comma(val)
+            element = DictAction._parse_iterable(val[:comma_idx])
+            values.append(element)
+            val = val[comma_idx + 1 :]
+        if is_tuple:
+            values = tuple(values)
+        return values
+
+    def __call__(self, parser, namespace, values, option_string=None):
+        options = {}
+        for kv in values:
+            key, val = kv.split("=", maxsplit=1)
+            options[key] = self._parse_iterable(val)
+        setattr(namespace, self.dest, options)