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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 from_enum(gtype, enum_value):
 """Turn an int back into an enum string. """


        pointer = vips_lib.vips_enum_nick(gtype, enum_value)
        if pointer == ffi.NULL:
            raise Error('value not in enum')

        return _to_string(pointer)