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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(self, msgid):
 """Yields the message header against each part from the message."""

        foldername, msgkey = msgid.split(SEPERATOR)
        folder = self.folder if foldername == "INBOX" else self._getfolder(foldername)
        # Now look up the message
        msg = folder[msgkey]
        msg.is_seen = True
        hdr = list(msg.items())
        for p in msg.walk():
            yield hdr,p
        return