old_contents: # -*- coding: utf-8 -*-
  
  VERSION = (1, 6, 1, 'final', 1)  # During development it is the next release
  RELEASE = False
  
  
  def get_version(version=None, release=None):
      """
      Derives a PEP386-compliant version number from VERSION. Adds '-dev',
      if it is not a release commit.
      """
      if version is None:
          version = VERSION
      if release is None:
          release = RELEASE
      assert len(version) == 5
      assert version[3] in ('alpha', 'beta', 'rc', 'final')
      # Now build the two parts of the version number:
      # main = X.Y[.Z]
      # sub = {a|b|c}N for alpha, beta and rc releases
      # Add '-dev', if it is not a release commit
      main_parts = 2 if version[2] == 0 else 3
      main = '.'.join(str(x) for x in version[:main_parts])
      if version[3] != 'final':
          mapping = {'alpha': 'a', 'beta': 'b', 'rc': 'c'}
          sub = mapping[version[3]] + str(version[4])
      else:
          sub = ''
      if not release:
          sub += '-dev'
      return main + sub
  
  
  def get_git_commit_id():
      """
      Catches the commit id of the git head.
      """
      try:
          git_head = open('.git/HEAD', 'r').read().rstrip()
          if git_head[:5] == 'ref: ':
              git_commit_id = open('.git/%s' % git_head[5:], 'r').read().rstrip()
          else:
              git_commit_id = git_head
      except IOError:
          git_commit_id = 'unknown'
      return str(git_commit_id)
  
new_contents: # -*- coding: utf-8 -*-
  
  VERSION = (2, 0, 0, 'alpha', 1)  # During development it is the next release
  RELEASE = False
  
  
  def get_version(version=None, release=None):
      """
      Derives a PEP386-compliant version number from VERSION. Adds '-dev',
      if it is not a release commit.
      """
      if version is None:
          version = VERSION
      if release is None:
          release = RELEASE
      assert len(version) == 5
      assert version[3] in ('alpha', 'beta', 'rc', 'final')
      # Now build the two parts of the version number:
      # main = X.Y[.Z]
      # sub = {a|b|c}N for alpha, beta and rc releases
      # Add '-dev', if it is not a release commit
      main_parts = 2 if version[2] == 0 else 3
      main = '.'.join(str(x) for x in version[:main_parts])
      if version[3] != 'final':
          mapping = {'alpha': 'a', 'beta': 'b', 'rc': 'c'}
          sub = mapping[version[3]] + str(version[4])
      else:
          sub = ''
      if not release:
          sub += '-dev'
      return main + sub
  
  
  def get_git_commit_id():
      """
      Catches the commit id of the git head.
      """
      try:
          git_head = open('.git/HEAD', 'r').read().rstrip()
          if git_head[:5] == 'ref: ':
              git_commit_id = open('.git/%s' % git_head[5:], 'r').read().rstrip()
          else:
              git_commit_id = git_head
      except IOError:
          git_commit_id = 'unknown'
      return str(git_commit_id)
  
subject: Bump version to 2.0a1-dev.