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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_method_docstring(cls, method_name):
 """ return method docstring if method docstring is empty we get docstring from parent :param method: :type method: :return: :rtype: """

    method = getattr(cls, method_name, None)
    if method is None:
        return
    docstrign = inspect.getdoc(method)
    if docstrign is None:
        for base in cls.__bases__:
            docstrign = get_method_docstring(base, method_name)
            if docstrign:
                return docstrign
        else:
            return None

    return docstrign