code: def validatetag(context):
      "Check to make sure that a tag exists for the current HEAD and it looks like a valid version number"
      # Validate that a Git tag exists for the current commit HEAD
      result = context.run("git describe --exact-match --tags $(git log -n1 --pretty='%h')")
      tag = result.stdout.rstrip()
  
      # Validate that the Git tag appears to be a valid version number
      ver_regex = re.compile('(\d+)\.(\d+)\.(\d+)')
      match = ver_regex.fullmatch(tag)
      if match is None:
          print('Tag {!r} does not appear to be a valid version number'.format(tag))
          sys.exit(-1)
      else:
          print('Tag {!r} appears to be a valid version number'.format(tag)f validatetag(context):
      "Check to make sure that a tag exists for the current HEAD and it looks like a valid version number"
      # Validate that a Git tag exists for the current commit HEAD
      result = context.run("git describe --exact-match --tags $(git log -n1 --pretty='%h')")
      tag = result.stdout.rstrip()
  
      # Validate that the Git tag appears to be a valid version number
      ver_regex = re.compile('(\d+)\.(\d+)\.(\d+)')
      match = ver_regex.fullmatch(tag)
      if match is None:
          print('Tag {!r} does not appear to be a valid version number'.format(tag))
          sys.exit(-1)
      else:
          print('Tag {!r} appears to be a valid version number'.format(tag))
docs: Check to make sure that a tag exists for the current HEAD and it looks like a valid version number