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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 encode_quopri(msg):
 """Encode the message's payload in quoted-printable. Also, add an appropriate Content-Transfer-Encoding header. """

    orig = msg.get_payload()
    encdata = _qencode(orig)
    msg.set_payload(encdata)
    msg['Content-Transfer-Encoding'] = 'quoted-printable'