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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 _remove_deactivated(contexts):
 """Remove deactivated handlers from the chain"""

    # Clean ctx handlers
    stack_contexts = tuple([h for h in contexts[0] if h.active])

    # Find new head
    head = contexts[1]
    while head is not None and not head.active:
        head = head.old_contexts[1]

    # Process chain
    ctx = head
    while ctx is not None:
        parent = ctx.old_contexts[1]

        while parent is not None:
            if parent.active:
                break
            ctx.old_contexts = parent.old_contexts
            parent = parent.old_contexts[1]

        ctx = parent

    return (stack_contexts, head)