code: def path_to_pattern(path, metadata=None):
      
      if not isinstance(path, str):
          return
  
      pattern = path
      if metadata:
          cache = metadata.get('cache')
          if cache:
              regex = next(c.get('regex') for c in cache if c.get('argkey') == 'urlpath')
              pattern = pattern.split(regex)[-1]
      return pattern
docs: Remove source information from path when using chaching
  
      Returns None if path is not str
  
      Parameters
      ----------
      path : str
          Path to data optionally containing format_strings
      metadata : dict, optional
          Extra arguments to the class, contains any cache information
  
      Returns
      -------
      pattern : str
          Pattern style path stripped of everything to the left of cache regex.