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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 is_colliding(self, other):
 """Check to see if two circles are colliding."""

        if isinstance(other, BoundingCircle):
            #Calculate the distance between two circles.
            distance = Vector2.distance(self.coords, other.coords)

            #Check to see if the sum of thier radi are greater than or equal to the distance.
            radi_sum = self.radius + other.radius

            if distance <= radi_sum:
                #There has been a collision
##                print "Distance: ", distance, "\nRadi Sum: ", radi_sum
##                print "Self Coords: ", self.coords, "\nOther Coords: ", other.coords
                return True

            #No collision.
            return False