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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_body_encoding(self):
 """Return the content-transfer-encoding used for body encoding. This is either the string `quoted-printable' or `base64' depending on the encoding used, or it is a function in which case you should call the function with a single argument, the Message object being encoded. The function should then set the Content-Transfer-Encoding header itself to whatever is appropriate. Returns "quoted-printable" if self.body_encoding is QP. Returns "base64" if self.body_encoding is BASE64. Returns conversion function otherwise. """

        assert self.body_encoding != SHORTEST
        if self.body_encoding == QP:
            return 'quoted-printable'
        elif self.body_encoding == BASE64:
            return 'base64'
        else:
            return encode_7or8bit