code: def tap_key(self, key, complementKey=None) :
  		
  
  		driver = self._current_browser()
  
  		if (complementKey is not None) :
  			ActionChains(driver).key_down(complementKey).send_keys(key).key_up(complementKey).perform()
  
  		else :
  			ActionChains(driver).send_keys(key).perform()
docs: Presses the specified `key`. The `complementKey` defines the key to hold
  		when pressing the specified `key`. For example, you could use ${VK_TAB} as `key` and
  		use ${VK_SHIFT} as `complementKey' in order to press Shift + Tab (back tab)
  
  		| =Argument= | =Description= | =Example= |
  		| key | the key to press | ${VK_F4} |
  		| complementKey | the key to hold while pressing the key passed in previous argument | ${VK_ALT} |