'Get pronoun from the pronoun marker in the text. This is used as
the callable for the re.sub function.
Args:
regex_match (MatchObject): the regular expression match.
Notes:
- `|s`, `|S`: Subjective form: he, she, it, He, She, It, They
- `|o`, `|O`: Objective form: him, her, it, Him, Her, It, Them
- `|p`, `|P`: Possessive form: his, her, its, His, Her, Its, Their
- `|a`, `|A`: Absolute Possessive form: his, hers, its, His, Hers, Its, Theirs'

def _get_pronoun(self, regex_match):

    typ = regex_match.group()[1]
    gender = self.attributes.get('gender', default='ambiguous')
    gender = (gender if (gender in ('male', 'female', 'neutral')) else 'ambiguous')
    pronoun = _GENDER_PRONOUN_MAP[gender][typ.lower()]
    return (pronoun.capitalize() if typ.isupper() else pronoun)
