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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 press_keycode(self, keycode, metastate=None):
 """Sends a press of keycode to the device. Android only. Possible keycodes & meta states can be found in http://developer.android.com/reference/android/view/KeyEvent.html Meta state describe the pressed state of key modifiers such as Shift, Ctrl & Alt keys. The Meta State is an integer in which each bit set to 1 represents a pressed meta key. For example - META_SHIFT_ON = 1 - META_ALT_ON = 2 | metastate=1 --> Shift is pressed | metastate=2 --> Alt is pressed | metastate=3 --> Shift+Alt is pressed - _keycode- - the keycode to be sent to the device - _metastate- - status of the meta keys """

        driver = self._current_application()
        driver.press_keycode(keycode, metastate)