old_contents: # imei.py - functions for handling International Mobile Equipment Identity
  #           (IMEI) numbers
  #
  # Copyright (C) 2010, 2011 Arthur de Jong
  #
  # This library is free software; you can redistribute it and/or
  # modify it under the terms of the GNU Lesser General Public
  # License as published by the Free Software Foundation; either
  # version 2.1 of the License, or (at your option) any later version.
  #
  # This library is distributed in the hope that it will be useful,
  # but WITHOUT ANY WARRANTY; without even the implied warranty of
  # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  # Lesser General Public License for more details.
  #
  # You should have received a copy of the GNU Lesser General Public
  # License along with this library; if not, write to the Free Software
  # Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  # 02110-1301 USA
  
  """Module for handling IMEI (International Mobile Equipment Identity)
  numbers, used to identify mobile phones.
  
  >>> is_valid('35686800-004141-20')
  True
  >>> is_valid('35-417803-685978-1') # incorrect check digit
  False
  >>> compact('35686800-004141-20')
  '3568680000414120'
  >>> format('354178036859789')
  '35-417803-685978-9'
  >>> format('35686800-004141', add_check_digit=True)
  '35-686800-004141-8'
  >>> imei_type('35686800-004141-20')
  'IMEISV'
  """
  
  
  def compact(number):
      """Convert the IMEI number to the minimal representation. This strips the
      number of any valid separators and removes surrounding whitespace."""
      return number.replace(' ', '').replace('-', '').strip().upper()
  
  
  def imei_type(number):
      """Check the passed number and returns 'IMEI', 'IMEISV' or None (for
      invalid) for checking the type of number passed."""
      try:
          number = compact(number)
      except:
          return None
      if len(number) == 14:  # IMEI without check digit
          return 'IMEI' if number.isdigit() else None
      if len(number) == 15:  # IMEI with check digit
          from stdnum import luhn
          return 'IMEI' if luhn.is_valid(number) else None
      elif len(number) == 16:
          return 'IMEISV' if number.isdigit() else None
      else:
          return None
  
  
  def is_valid(number):
      """Checks to see if the number provided is a valid IMEI (or IMEISV)
      number."""
      return imei_type(number) is not None
  
  
  def format(number, separator='-', add_check_digit=False):
      """Reformat the passed number to the standard format."""
      number = compact(number)
      if len(number) == 14 and add_check_digit:
          from stdnum import luhn
          number += luhn.calc_check_digit(number)
      number = (number[:2], number[2:8], number[8:14], number[14:])
      return separator.join(x for x in number if x)
  
new_contents: # imei.py - functions for handling International Mobile Equipment Identity
  #           (IMEI) numbers
  #
  # Copyright (C) 2010, 2011 Arthur de Jong
  #
  # This library is free software; you can redistribute it and/or
  # modify it under the terms of the GNU Lesser General Public
  # License as published by the Free Software Foundation; either
  # version 2.1 of the License, or (at your option) any later version.
  #
  # This library is distributed in the hope that it will be useful,
  # but WITHOUT ANY WARRANTY; without even the implied warranty of
  # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  # Lesser General Public License for more details.
  #
  # You should have received a copy of the GNU Lesser General Public
  # License along with this library; if not, write to the Free Software
  # Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  # 02110-1301 USA
  
  """Module for handling IMEI (International Mobile Equipment Identity)
  numbers, used to identify mobile phones.
  
  >>> is_valid('35686800-004141-20')
  True
  >>> is_valid('35-417803-685978-1') # incorrect check digit
  False
  >>> compact('35686800-004141-20')
  '3568680000414120'
  >>> format('354178036859789')
  '35-417803-685978-9'
  >>> format('35686800-004141', add_check_digit=True)
  '35-686800-004141-8'
  >>> imei_type('35686800-004141-20')
  'IMEISV'
  >>> split('35686800-004141')
  ('35686800', '004141', '')
  """
  
  
  def compact(number):
      """Convert the IMEI number to the minimal representation. This strips the
      number of any valid separators and removes surrounding whitespace."""
      return number.replace(' ', '').replace('-', '').strip().upper()
  
  
  def imei_type(number):
      """Check the passed number and returns 'IMEI', 'IMEISV' or None (for
      invalid) for checking the type of number passed."""
      try:
          number = compact(number)
      except:
          return None
      if len(number) == 14:  # IMEI without check digit
          return 'IMEI' if number.isdigit() else None
      if len(number) == 15:  # IMEI with check digit
          from stdnum import luhn
          return 'IMEI' if luhn.is_valid(number) else None
      elif len(number) == 16:
          return 'IMEISV' if number.isdigit() else None
      else:
          return None
  
  
  def is_valid(number):
      """Checks to see if the number provided is a valid IMEI (or IMEISV)
      number."""
      return imei_type(number) is not None
  
  
  def split(number):
      """Split the number into a Type Allocation Code (TAC), serial number
      and either the checksum (for IMEI) or the software version number (for
      IMEISV)."""
      number = compact(number)
      return (number[:8], number[8:14], number[14:])
  
  
  def format(number, separator='-', add_check_digit=False):
      """Reformat the passed number to the standard format."""
      number = compact(number)
      if len(number) == 14 and add_check_digit:
          from stdnum import luhn
          number += luhn.calc_check_digit(number)
      number = (number[:2], number[2:8], number[8:14], number[14:])
      return separator.join(x for x in number if x)
  
subject: implement an imei.split() function that splits the number into a TAC, serial number and checksum or software version