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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 pressKeyCode(self, keycode, metaState=0):
        '''By default no meta state'''
        if self.uiAutomatorHelper:
            if DEBUG_UI_AUTOMATOR_HELPER:
                print >> sys.stderr, "pressKeyCode(%d, %d)" % (keycode, metaState)
            self.uiAutomatorHelper.pressKeyCode(keycode, metaState)
        else:
            warnings.warn("pressKeyCode only implemented using UiAutomatorHelper.  Use AdbClient.type() instead")