How can I call a function within a class?

I have this code which calculates the distance between two coordinates. The two functions are both within the same class.

However, how do I call the function distToPoint in the function isNear?

class Coordinates:
    def distToPoint(self, p):
        """
        Use pythagoras to find distance
        (a^2 = b^2 + c^2)
        """
        ...

    def isNear(self, p):
        distToPoint(self, p)
        ...