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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 split(cls, n, contiguous, can_query=itertools.chain(itertools.repeat(True, 50), itertools.repeat(False)).next, _app=None):
 # pylint: disable=g-doc-args """Splits the complete NamespaceRange into n equally-sized NamespaceRanges. Args: n: The maximum number of NamespaceRanges to return. Fewer than n namespaces may be returned. contiguous: If True then the returned NamespaceRanges will cover the entire space of possible namespaces (i.e. from MIN_NAMESPACE to MAX_NAMESPACE) without gaps. If False then the returned NamespaceRanges may exclude namespaces that don't appear in the datastore. can_query: A function that returns True if split() can query the datastore to generate more fair namespace range splits, and False otherwise. If not set then split() is allowed to make 50 datastore queries. Returns: A list of at most n NamespaceRanges representing a near-equal distribution of actual existant datastore namespaces. The returned list will be sorted lexographically. Raises: ValueError: if n is < 1. """

    if n < 1:
      raise ValueError('n must be >= 1')

    ranges = None
    if can_query():
      if not contiguous:
        ns_keys = get_namespace_keys(_app, n + 1)
        if not ns_keys:
          return []
        else:
          if len(ns_keys) <= n:
            # If you have less actual namespaces than number of NamespaceRanges
            # to return, then just return the list of those namespaces.
            ns_range = []
            for ns_key in ns_keys:
              ns_range.append(NamespaceRange(ns_key.name() or '',
                                             ns_key.name() or '',
                                             _app=_app))
            return sorted(ns_range,
                          key=lambda ns_range: ns_range.namespace_start)
          # Use the first key and save the initial normalized_start() call.
          ranges = [NamespaceRange(ns_keys[0].name() or '', _app=_app)]
      else:
        ns_range = NamespaceRange(_app=_app).normalized_start()
        if ns_range is None:
          return [NamespaceRange(_app=_app)]
        ranges = [ns_range]
    else:
      ranges = [NamespaceRange(_app=_app)]

    singles = []
    while ranges and (len(ranges) + len(singles)) < n:
      namespace_range = ranges.pop(0)
      if namespace_range.is_single_namespace:
        singles.append(namespace_range)
      else:
        left, right = namespace_range.split_range()
        if can_query():
          right = right.normalized_start()
        if right is not None:
          ranges.append(right)
        ranges.append(left)
    ns_ranges = sorted(singles + ranges,
                       key=lambda ns_range: ns_range.namespace_start)

    if contiguous:
      if not ns_ranges:
        # This condition is possible if every namespace was deleted after the
        # first call to ns_range.normalized_start().
        return [NamespaceRange(_app=_app)]

      continuous_ns_ranges = []
      for i in range(len(ns_ranges)):
        if i == 0:
          namespace_start = MIN_NAMESPACE
        else:
          namespace_start = ns_ranges[i].namespace_start

        if i == len(ns_ranges) - 1:
          namespace_end = MAX_NAMESPACE
        else:
          namespace_end = _ord_to_namespace(
              _namespace_to_ord(ns_ranges[i+1].namespace_start) - 1)

        continuous_ns_ranges.append(NamespaceRange(namespace_start,
                                                   namespace_end,
                                                   _app=_app))
      return continuous_ns_ranges
    else:
      return ns_ranges