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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 normalized_start(self):
 """Returns a NamespaceRange with leading non-existant namespaces removed. Returns: A copy of this NamespaceRange whose namespace_start is adjusted to exclude the portion of the range that contains no actual namespaces in the datastore. None is returned if the NamespaceRange contains no actual namespaces in the datastore. """

    namespaces_after_key = list(self.make_datastore_query().Run(limit=1))

    if not namespaces_after_key:
      return None

    namespace_after_key = namespaces_after_key[0].name() or ''
    return NamespaceRange(namespace_after_key,
                          self.namespace_end,
                          _app=self.app)