docs: def version_from_frame(frame):
      """
      Given a ``frame``, obtain the version number of the module running there.
      """
  
      module = getmodule(frame)
      if module is None:
          s = "<unknown from {0}:{1}>"
          return s.format(frame.f_code.co_filename, frame.f_lineno)
  
      module_name = module.__name__
  
      variable = "AUTOVERSION_{}".format(module_name.upper())
      override = os.environ.get(variable, None)
      if override is not None:
          return override
  
      while True:
          try:
              get_distribution(module_name)
          except DistributionNotFound:
              # Look at what's to the left of "."
              module_name, dot, _ = module_name.partition(".")
              if dot == "":
                  # There is no dot, nothing more we can do.
                  break
          else:
              return getversion(module_name)
  
      return None