class_docstr: A mention (possible anaphor) inherite from spacy Span class with additional informations
code: def embedding(self):
      return np.concatenate(
          [self.spans_embeddings, self.words_embeddings], axis=0
      )
  
imports: import re
  import io
  from six import string_types, integer_types
  from spacy.tokens import Span, Token
  from neuralcoref.train.compat import unicode_
  from neuralcoref.train.utils import encode_distance, parallel_process
  import spacy
  import numpy
label_desc: Use image node_id 8 for calling the Mention obj's underlying member method code with example usage: obj.embedding() and returns: np