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 # This Source Code Form is subject to the terms of the Mozilla Public

 # License, v. 2.0. If a copy of the MPL was not distributed with this

 # file, You can obtain one at http://mozilla.org/MPL/2.0/.

 # Prints the pre-release version suffix based on the version string

 #

 # Examples:

 # 2.1a3    > " 2.1 Alpha 3"

 # 2.1a3pre > ""

 # 3.2b4    > " 3.2 Beta 4"

 # 3.2b4pre > ""

 from __future__ import print_function

 import sys

 import re

 def get_prerelease_suffix(version):

   """ Returns the prerelease suffix from the version string argument """

   def mfunc(m):

     return " {0} {1} {2}".format(m.group('prefix'),

                                  {'a': 'Alpha', 'b': 'Beta'}[m.group('c')],

                                  m.group('suffix'))

   result, c = re.subn(r'^(?P<prefix>(\d+\.)*\d+)(?P<c>[ab])(?P<suffix>\d+)$',

                       mfunc, version)

   if c != 1:

     return ''

   return result

 if len(sys.argv) == 2:

   print(get_prerelease_suffix(sys.argv[1]))