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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 get_fields_by_class(cls, field_class):
 """ Return a list of field names matching a field class :param field_class: field class object :return: list """


        ret = []

        for key, val in getattr(cls, '_fields').items():
            if isinstance(val, field_class):
                ret.append(key)
        return ret