code: def from_home_db_json(cls, identifier, key_mapping=None):  # pragma: no cover
          
          return cls.from_json(
              json_file=cls.path_db_json, json_path=identifier, key_mapping=key_mapping)
docs: Read credential from $HOME/.db.json file.
  
          :type identifier: str
          :param identifier: str, database identifier.
  
          :type key_mapping: Dict[str, str]
          :param key_mapping: dict
  
          ``.db.json````::
  
              {
                  "identifier1": {
                      "host": "example.com",
                      "port": 1234,
                      "database": "test",
                      "username": "admin",
                      "password": "admin",
                  },
                  "identifier2": {
                      ...
                  }
              }