title: perspective transformation in Python: from rectangular to trapezoid
body: <p>I am looking for a python function or library that can convert coordinates of rectangle to trapezoid coordinates. So far I found the relevant problem here: <a href="https://math.stackexchange.com/questions/13404/mapping-irregular-quadrilateral-to-a-rectangle">https://math.stackexchange.com/questions/13404/mapping-irregular-quadrilateral-to-a-rectangle</a> but no code is available. Is there any package or any function in Python that can do this?</p>