Class inside a class in Python : <p>How can i call a class inside a class in Python? For example:</p>

<pre><code>class POINT:
    def __init__(self, x, y):
        self.x = x
        self.y = y

class CIRCLE:
    def __init__(self, x, y, radius):
        self.x = x
        self.y = y
        self.radius = radius
</code></pre>

<p>I want to call POINT class in CIRCLE.
Thanks for answers.</p>
