code: def _get_span(s, pattern):
      
      i, j = -1, -1
  
      match = pattern.match(s)
      if not match:
          return i, j
  
      for group_name in pattern.groupindex:
          i, j = match.span(group_name)
          if (i, j) != (-1, -1):
              return i, j
  
      return i, j
docs: Return the span of the first group that matches the pattern.