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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 get_comments_are_open(instance):
 """ Check if comments are open for the instance """

    if not IS_INSTALLED:
        return False

    try:
        # Get the moderator which is installed for this model.
        mod = moderator._registry[instance.__class__]
    except KeyError:
        # No moderator = no restrictions
        return True

    # Check the 'enable_field', 'auto_close_field' and 'close_after',
    # by reusing the basic Django policies.
    return CommentModerator.allow(mod, None, instance, None)