import math


def ellipse_perimeter(maj_ax, min_ax):
    """ Returns an estimate for the perimeter of an ellipse of semi-major axis
    maj_ax and semi-minor axis min_ax"""
    # https://www.universoformulas.com/matematicas/geometria/perimetro-elipse/
    H = ((maj_ax - min_ax)/(maj_ax + min_ax))**2
    return math.pi*(maj_ax + min_ax)*(1 + 3*H/(10 + (4 - 3*H)**.5))