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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def unflatten(d, key_as_tuple=True, delim='.', list_of_dicts=None, deepcopy=True):
 r""" unflatten dictionary with keys as tuples or delimited strings Parameters d : dict key_as_tuple : bool if true, keys are tuples, else, keys are delimited strings delim : str if keys are strings, then split by delim list_of_dicts: str or None if key starts with this treat as a list Examples -------- {'a': {'b': 1, 'c': 2}} {'a': {'b': 1, 'c': 2}} {'a': [{'b': 2}, {'a': 1}]} Traceback (most recent call last):
 KeyError: "child conflict for path: ('a', 'b'); 2 and {'c': 1}" """

    if not d:
        return d

    if deepcopy:
        try:
            d = copy.deepcopy(d)
        except Exception:
            warnings.warn(
                'error in deepcopy, so using references to input dict')

    if key_as_tuple:
        result = d.pop(()) if () in d else {}
    else:
        result = d.pop('') if '' in d else {}

    for key, value in d.items():

        if not isinstance(key, tuple) and key_as_tuple:
            raise ValueError(
                'key not tuple and key_as_tuple set to True: {}'.format(key))
        elif not isinstance(key, basestring) and not key_as_tuple:
            raise ValueError(
                'key not string and key_as_tuple set to False: {}'.format(key))
        elif isinstance(key, basestring) and not key_as_tuple:
            parts = key.split(delim)
        else:
            parts = key

        d = result
        for part in parts[:-1]:
            if part not in d:
                d[part] = {}
            d = d[part]
        if not is_dict_like(d):
            v1, v2 = sorted([str(d), str({parts[-1]: value})])
            raise KeyError("child conflict for path: "
                           "{0}; {1} and {2}".format(parts[:-1], v1, v2))
        elif parts[-1] in d:
            try:
                value = merge([d[parts[-1]], value])
            except Exception:
                v1, v2 = sorted([str(value), str(d[parts[-1]])])
                raise KeyError("child conflict for path: "
                               "{0}; {1} and {2}".format(parts, v1, v2))
        d[parts[-1]] = value

    if list_of_dicts is not None:
        result = _recreate_lists(result, list_of_dicts)
        # if is_dict_like(result):
        #    if all([str(k).startswith(list_of_dicts) for k in result.keys()]):
        #         result = [result[k] for k in sorted(list(result.keys()),
        # key=lambda x: int(x.replace(list_of_dicts, '')))]

    return result