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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_default_hook(default_hook, hook):
 """Checks whether a specific hook is in its default state. Args: cls: A ndb.model.Model class. default_hook: Callable specified by ndb internally (do not override). hook: The hook defined by a model class using _post_*_hook. Raises: TypeError if either the default hook or the tested hook are not callable. """

    if not hasattr(default_hook, '__call__'):
      raise TypeError('Default hooks for ndb.model.Model must be callable')
    if not hasattr(hook, '__call__'):
      raise TypeError('Hooks must be callable')
    return default_hook.im_func is hook.im_func