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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 get_child_at(self, x, y, bAllowTransparency = True):
 """ Get the child window located at the given coordinates. If no such window exists an exception is raised. @see: L{get_children} @type x: int @param x: Horizontal coordinate. @type y: int @param y: Vertical coordinate. @type bAllowTransparency: bool @param bAllowTransparency: If C{True} transparent areas in windows are ignored, returning the window behind them. If C{False} transparent areas are treated just like any other area. @rtype: L{Window} @return: Child window at the requested position, or C{None} if there is no window at those coordinates. """

        try:
            if bAllowTransparency:
                hWnd = win32.RealChildWindowFromPoint( self.get_handle(), (x, y) )
            else:
                hWnd = win32.ChildWindowFromPoint( self.get_handle(), (x, y) )
            if hWnd:
                return self.__get_window(hWnd)
        except WindowsError:
            pass
        return None