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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 complete_vhwa_command(self, command):
 """Signals that the Video HW Acceleration command has completed. in command of type str Pointer to VBOXVHWACMD containing the completed command. """

        if not isinstance(command, basestring):
            raise TypeError("command can only be an instance of type basestring")
        self._call("completeVHWACommand",
                     in_p=[command])