old_contents: # coding: utf-8
  from __future__ import unicode_literals, division, absolute_import, print_function
  
  import os
  
  from .._errors import pretty_message
  from .._types import type_name, int_types
  
  
  __all__ = [
      'rand_bytes',
  ]
  
  
  def rand_bytes(length):
      """
      Returns a number of random bytes suitable for cryptographic purposes
  
      :param length:
          The desired number of bytes
  
      :raises:
          ValueError - when any of the parameters contain an invalid value
          TypeError - when any of the parameters are of the wrong type
          OSError - when an error is returned by OpenSSL
  
      :return:
          A byte string
      """
  
      if not isinstance(length, int_types):
          raise TypeError(pretty_message(
              '''
              length must be an integer, not %s
              ''',
              type_name(length)
          ))
  
      if length < 1:
          raise ValueError('length must be greater than 0')
  
      if length > 1024:
          raise ValueError('length must not be greater than 1024')
  
      return os.urandom(length)
  
new_contents: # coding: utf-8
  from __future__ import unicode_literals, division, absolute_import, print_function
  
  import os
  
  from ._errors import pretty_message
  from ._types import type_name, int_types
  
  
  __all__ = [
      'rand_bytes',
  ]
  
  
  def rand_bytes(length):
      """
      Returns a number of random bytes suitable for cryptographic purposes
  
      :param length:
          The desired number of bytes
  
      :raises:
          ValueError - when any of the parameters contain an invalid value
          TypeError - when any of the parameters are of the wrong type
          OSError - when an error is returned by OpenSSL
  
      :return:
          A byte string
      """
  
      if not isinstance(length, int_types):
          raise TypeError(pretty_message(
              '''
              length must be an integer, not %s
              ''',
              type_name(length)
          ))
  
      if length < 1:
          raise ValueError('length must be greater than 0')
  
      if length > 1024:
          raise ValueError('length must not be greater than 1024')
  
      return os.urandom(length)
  
subject: Fix imports