def get_config(self, retrieve="<STR_LIT:all>"):
raise NotImplementedError<EOL>
Return the configuration of a device.

Args:
    retrieve(string): Which configuration type you want to populate, default is all of them.
                      The rest will be set to "".

Returns:
  The object returned is a dictionary with a key for each configuration store:

    - running(string) - Representation of the native running configuration
    - candidate(string) - Representation of the native candidate configuration. If the
      device doesnt differentiate between running and startup configuration this will an
      empty string
    - startup(string) - Representation of the native startup configuration. If the
      device doesnt differentiate between running and startup configuration this will an
      empty string