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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_function_class(function_name):
 """ Return the type for the requested function :param function_name: the function to return :return: the type for that function (i.e., this is a class, not an instance) """


    if function_name in _known_functions:

        return _known_functions[function_name]

    else:

        raise UnknownFunction("Function %s is not known. Known functions are: %s" %
                              (function_name, ",".join(_known_functions.keys())))