code: def setColorAlpha(self, fixed=None, proportional=None):
  		
  		if fixed!=None:
  			self.color.set_alpha(fixed)
  		elif proportional!=None:
  			self.color.set_alpha(self.color.get_alpha()*proportional)
docs: Change the alpha of the current :py:class:`Color`.
  		
  		:param fixed: Set the absolute 0-1 value of the alpha.
  		:param proportional: Set the relative value of the alpha (Es: If the current alpha is 0.8, a proportional value of 0.5 will set the final value to 0.4).
  		:rtype: Nothing.