from typing import Dict, List, Tuple from ...pipeline import Lemmatizer from ...tokens import Token class ItalianLemmatizer(Lemmatizer): """This lemmatizer was adapted from the Polish one (version of April 2021). It implements lookup lemmatization based on the morphological lexicon morph-it (Baroni and Zanchetta). The table lemma_lookup with non-POS-aware entries is used as a backup for words that aren't handled by morph-it.""" @classmethod def get_lookups_config(cls, mode: str) -> Tuple[List[str], List[str]]: if mode == "pos_lookup": required = [ "lemma_lookup_num", "lemma_lookup_det", "lemma_lookup_adp", "lemma_lookup_adj", "lemma_lookup_noun", "lemma_lookup_pron", "lemma_lookup_verb", "lemma_lookup_aux", "lemma_lookup_adv", "lemma_lookup_other", "lemma_lookup", ] return (required, []) else: return super().get_lookups_config(mode) def pos_lookup_lemmatize(self, token: Token) -> List[str]: string = token.text univ_pos = token.pos_ morphology = token.morph.to_dict() lookup_pos = univ_pos.lower() if univ_pos == "PROPN": lookup_pos = "noun" elif univ_pos == "PART": lookup_pos = "pron" lookup_table = self.lookups.get_table("lemma_lookup_" + lookup_pos, {}) if univ_pos == "NOUN": return self.lemmatize_noun(string, morphology, lookup_table) else: if univ_pos != "PROPN": string = string.lower() if univ_pos == "DET": return self.lemmatize_det(string, morphology, lookup_table) elif univ_pos == "PRON": return self.lemmatize_pron(string, morphology, lookup_table) elif univ_pos == "ADP": return self.lemmatize_adp(string, morphology, lookup_table) elif univ_pos == "ADJ": return self.lemmatize_adj(string, morphology, lookup_table) else: lemma = lookup_table.get(string, "") if not lemma: lookup_table = self.lookups.get_table("lemma_lookup_other") lemma = lookup_table.get(string, "") if not lemma: lookup_table = self.lookups.get_table( "lemma_lookup" ) # "legacy" lookup table lemma = lookup_table.get(string, string.lower()) return [lemma] def lemmatize_det( self, string: str, morphology: dict, lookup_table: Dict[str, str] ) -> List[str]: if string in [ "l'", "lo", "la", "i", "gli", "le", ]: return ["il"] if string in ["un'", "un", "una"]: return ["uno"] return [lookup_table.get(string, string)] def lemmatize_pron( self, string: str, morphology: dict, lookup_table: Dict[str, str] ) -> List[str]: if string in [ "l'", "li", "la", "gli", "le", ]: return ["lo"] if string in ["un'", "un", "una"]: return ["uno"] lemma = lookup_table.get(string, string) if lemma == "alcun": lemma = "alcuno" elif lemma == "qualcun": lemma = "qualcuno" return [lemma] def lemmatize_adp( self, string: str, morphology: dict, lookup_table: Dict[str, str] ) -> List[str]: if string == "d'": return ["di"] return [lookup_table.get(string, string)] def lemmatize_adj( self, string: str, morphology: dict, lookup_table: Dict[str, str] ) -> List[str]: lemma = lookup_table.get(string, string) if lemma == "alcun": lemma = "alcuno" elif lemma == "qualcun": lemma = "qualcuno" return [lemma] def lemmatize_noun( self, string: str, morphology: dict, lookup_table: Dict[str, str] ) -> List[str]: # this method is case-sensitive, in order to work # for incorrectly tagged proper names if string != string.lower(): if string.lower() in lookup_table: return [lookup_table[string.lower()]] elif string in lookup_table: return [lookup_table[string]] return [string.lower()] return [lookup_table.get(string, string)]