def centroid(*args):

    from sympy.geometry import Polygon, Segment, Point
    if args:
        if all(isinstance(g, Point) for g in args):
            c = Point(0, 0)
            for g in args:
                c += g
            den = len(args)
        elif all(isinstance(g, Segment) for g in args):
            c = Point(0, 0)
            L = 0
            for g in args:
                l = g.length
                c += g.midpoint*l
                L += l
            den = L
        elif all(isinstance(g, Polygon) for g in args):
            c = Point(0, 0)
            A = 0
            for g in args:
                a = g.area
                c += g.centroid*a
                A += a
            den = A
        c /= den
        return c.func(*[i.simplify() for i in c.args])
Find the centroid (center of mass) of the collection containing only Points,
dataset/ETHPy150Open sympy/sympy/sympy/geometry/util.py/centroid