code: def visit_exact_match_value(self, node, fieldnames=None):
          
          if not fieldnames:
              fieldnames = ['_all']
          else:
              fieldnames = force_list(fieldnames)
  
          if ElasticSearchVisitor.KEYWORD_TO_ES_FIELDNAME['exact-author'] == fieldnames[0]:
              return self._generate_exact_author_query(node.value)
  
          elif ElasticSearchVisitor.KEYWORD_TO_ES_FIELDNAME['type-code'] == fieldnames[0]:
              return self._generate_type_code_query(node.value)
  
          elif ElasticSearchVisitor.KEYWORD_TO_ES_FIELDNAME['journal'] == fieldnames:
              return self._generate_journal_nested_queries(node.value)
  
          bai_fieldnames = self._generate_fieldnames_if_bai_query(
              node.value,
              bai_field_variation=FieldVariations.raw,
              query_bai_field_if_dots_in_name=False
          )
  
          if ElasticSearchVisitor.KEYWORD_TO_ES_FIELDNAME['date'] == fieldnames:
              term_queries = []
              for field in fieldnames:
                  term_query =  \
                      {'term': {field: _truncate_date_value_according_on_date_field(field, node.value).dumps()}}
  
                  term_queries.append(
                      generate_nested_query(ElasticSearchVisitor.DATE_NESTED_QUERY_PATH, term_query)
                      if field in ElasticSearchVisitor.DATE_NESTED_FIELDS
                      else term_query
                  )
          elif ElasticSearchVisitor.KEYWORD_TO_ES_FIELDNAME['author'] in fieldnames:
              term_queries = [
                  generate_nested_query(ElasticSearchVisitor.AUTHORS_NESTED_QUERY_PATH, {'term': {field: node.value}})
                  for field in (bai_fieldnames or fieldnames)
              ]
          else:
              term_queries = [{'term': {field: node.value}} for field in (bai_fieldnames or fieldnames)]
  
          return wrap_queries_in_bool_clauses_if_more_than_one(term_queries, use_must_clause=False)
docs: Generates a term query (exact search in ElasticSearch).