docstr: Return the string bounding box.
code: def get_str_bbox(self, s):
      """Return the string bounding box."""
      return self.get_str_bbox_and_descent(s)[:4]
  
imports: from collections import namedtuple
  import logging
  import re
  from ._mathtext_data import uni2type1
label_desc: Use image node_id 5 for calling the AFM obj's underlying member method code with example usage: obj.get_str_bbox(s) and returns: self