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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 polygon_triangulate(tri_idx, *args):
 """ Triangulates a monotone polygon defined by a list of vertices. The input vertices must form a convex polygon and must be arranged in counter-clockwise order. :param tri_idx: triangle numbering start value :type tri_idx: int :param args: list of Vertex objects :type args: Vertex :return: list of Triangle objects :rtype: list """

    # Initialize variables
    tidx = 0
    triangles = []

    # Generate triangles
    for idx in range(1, len(args) - 1):
        tri = Triangle()
        tri.id = tri_idx + tidx
        tri.add_vertex(args[0], args[idx], args[idx + 1])
        triangles.append(tri)
        tidx += 1

    # Return generated triangles
    return triangles