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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 body(self):
 """Yields the encoded body."""

        for chunk in self.gen_chunks(self.envelope.file_open(self.name)):
            yield chunk
        for chunk in self.gen_chunks(self.data):
            yield chunk
        for chunk in self.gen_chunks(self.envelope.file_close()):
            yield chunk
        for chunk in self.close():
            yield chunk