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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 SendVoicemail(self, Username):
 """Sends a voicemail to a specified user. :Parameters: Username : str Skypename of the user. :note: Should return a `Voicemail` object. This is not implemented yet. """

        if self._Api.protocol >= 6:
            self._DoCommand('CALLVOICEMAIL %s' % Username)
        else:
            self._DoCommand('VOICEMAIL %s' % Username)