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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 _ord_to_namespace(n, _max_length=None):
 """Convert a namespace ordinal to a namespace string. Converts an int, representing the sequence number of a namespace ordered lexographically, into a namespace string. '' '-' '--' '---' Args: n: A number representing the lexographical ordering of a namespace. _max_length: The maximum namespace length. Returns: A string representing the nth namespace in lexographical order. """

  if _max_length is None:
    _max_length = MAX_NAMESPACE_LENGTH

  length = _LEX_DISTANCE[_max_length - 1]
  if n == 0:
    return ''
  n -= 1
  return (NAMESPACE_CHARACTERS[n / length] +
          _ord_to_namespace(n % length, _max_length - 1))