def splitPolygons(s):
    """ Return a list of polygons from s. Separator is a blank line.
        Separation lines with blanks are digested as well.

        Args:
            s (string): string defining polygon(s) separated by a blank
                line. One vertex per line

        Returns:
            list with polygons
    """
    ss = "\n".join([l if l.strip() else '\n'
            for l in s.strip().splitlines()])
    return ss.split('\n\n')