'Returns True if self and o are the same mathematical entities.
Examples
>>> from sympy import Plane, Point3D
>>> a = Plane(Point3D(1, 2, 3), normal_vector=(1, 1, 1))
>>> b = Plane(Point3D(1, 2, 3), normal_vector=(2, 2, 2))
>>> c = Plane(Point3D(1, 2, 3), normal_vector=(-1, 4, 6))
>>> a.equals(a)
True
>>> a.equals(b)
True
>>> a.equals(c)
False'

def equals(self, o):

    if isinstance(o, Plane):
        a = self.equation()
        b = o.equation()
        return simplify((a / b)).is_constant()
    else:
        return False
