@staticmethod<EOL><INDENT>def from_json(f: TextIO) -> '<STR_LIT>':<DEDENT>
o = json.load(f)<EOL>return PrecalculatedTextMeasurer(o['<STR_LIT>'],<EOL>o['<STR_LIT>'],<EOL>o['<STR_LIT>'])<EOL>
Return a PrecalculatedTextMeasurer given a JSON stream.

        See precalculate_text.py for details on the required format.