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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 spec_from_json_dict( json_dict # type: Dict[str, Any] ):
 """ Turns a dictionary into the appropriate object. :param dict json_dict: A dictionary with properties. :returns: An initialised instance of the appropriate FieldSpec subclass. """

    if 'ignored' in json_dict:
        return Ignore(json_dict['identifier'])
    type_str = json_dict['format']['type']
    spec_type = cast(FieldSpec, FIELD_TYPE_MAP[type_str])
    return spec_type.from_json_dict(json_dict)