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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 exec_module(self, module):
 """Execute the module."""

        code = self.get_code(module.__name__)
        if code is None:
            raise ImportError('cannot load module {!r} when get_code() '
                              'returns None'.format(module.__name__))

        exec(code, module.__dict__)