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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 qhull_cmd(cmd, options, points):
 """ Generalized helper method to perform a qhull based command. Args: cmd: Command to perform. Supported commands are qconvex, qdelaunay and qvoronoi. options: Options to be provided for qhull command. See specific methods for info on supported options. Up to two options separated by spaces are supported. points: Sequence of points as input to qhull command. Returns: Output as a list of strings. E.g., ['4', '0 2', '1 0', '2 3 ', '3 1'] """

    prep_str = [str(len(points[0])), str(len(points))]
    prep_str.extend([' '.join(map(repr, row)) for row in points])
    output = getattr(hull, cmd)(options, "\n".join(prep_str))
    return list(map(str.strip, output.strip().split("\n")))