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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 UInt32():
 """Returns a pseudo-random 32-bit unsigned integer."""

  with _mutex:
    try:
      return _random_buffer.pop()
    except IndexError:
      data = os.urandom(struct.calcsize("=L") * _random_buffer_size)
      _random_buffer.extend(
          struct.unpack("=" + "L" * _random_buffer_size, data))
      return _random_buffer.pop()