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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 PlaceCall(self, *Targets):
 """Places a call to a single user or creates a conference call. :Parameters: Targets : str One or more call targets. If multiple targets are specified, a conference call is created. The call target can be a Skypename, phone number, or speed dial code. :return: A call object. :rtype: `call.Call` """

        calls = self.ActiveCalls
        reply = self._DoCommand('CALL %s' % ', '.join(Targets))
        # Skype for Windows returns the call status which gives us the call Id;
        if reply.startswith('CALL '):
            return Call(self, chop(reply, 2)[1])
        # On linux we get 'OK' as reply so we search for the new call on
        # list of active calls.
        for c in self.ActiveCalls:
            if c not in calls:
                return c
        raise SkypeError(0, 'Placing call failed')