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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 compile(cls, code, path=None, libraries=None, contract_name='', extra_args=None):
 """ Return the binary of last contract in code. """

        result = cls._code_or_path(
            code,
            path,
            contract_name,
            libraries,
            'bin',
            extra_args)
        return result['bin']