code: def read_version(path):
      
      version = None
      if os.path.exists(path):
          version = open(path, 'r', encoding='utf-8').read().strip()
  
      if version:
          return re.sub(r'^python-', '', version)
  
      return version
docs: Attempts to read a python version string from a runtime.txt file
  
      :param path: to source of the string
      :return: python version
      :rtype: unicode or None