old_contents: import subprocess
  from git_release import errors, git_helpers
  
  def _parse_tag(tag):
      major, minor =  tag.split('.')
      return int(major), int(minor)
  
  def _increment_tag(tag, release_type):
      major, minor = _parse_tag(tag)
      if release_type == 'major':
          new_major = major + 1
          new_minor = 0
      else:
          new_major = major
          new_minor = minor + 1
  
      return '{}.{}'.format(new_major, new_minor)
  
  def release(release_type, signed):
      if not git_helpers.is_master():
          raise errors.NotMasterException("Current branch is not master.\nAborting.")
  
      tag = git_helpers.get_current_tag()
      if not tag:
          raise errors.NoTagException("Unable to get current tag.\nAborting.")
  
      new_tag = _increment_tag(tag)
  
      git_helpers.tag(signed, new_tag)
  
new_contents: import subprocess
  from git_release import errors, git_helpers
  
  def _parse_tag(tag):
      major, minor =  tag.split('.')
      return int(major), int(minor)
  
  def _increment_tag(tag, release_type):
      major, minor = _parse_tag(tag)
      if release_type == 'major':
          new_major = major + 1
          new_minor = 0
      else:
          new_major = major
          new_minor = minor + 1
  
      return '{}.{}'.format(new_major, new_minor)
  
  def release(release_type, signed):
      if not git_helpers.is_master():
          raise errors.NotMasterException("Current branch is not master.\nAborting.")
  
      tag = git_helpers.get_current_tag()
      if not tag:
          raise errors.NoTagException("Unable to get current tag.\nAborting.")
  
      new_tag = _increment_tag(tag, release_type)
  
      git_helpers.tag(signed, new_tag)
  
subject: Add missing argument to _increment_tag call