def lookup(self, keys, read_consistency=None, transaction=None):
conn = self.get_conn()<EOL>body = {'<STR_LIT>': keys}<EOL>if read_consistency:<EOL><INDENT>body['<STR_LIT>'] = read_consistency<EOL><DEDENT>if transaction:<EOL><INDENT>body['<STR_LIT>'] = transaction<EOL><DEDENT>resp = (conn<EOL>.projects()<EOL>.lookup(projectId=self.project_id, body=body)<EOL>.execute(num_retries=self.num_retries))<EOL>return resp<EOL>
Lookup some entities by key.

.. seealso::
    https://cloud.google.com/datastore/docs/reference/rest/v1/projects/lookup

:param keys: the keys to lookup.
:type keys: list
:param read_consistency: the read consistency to use. default, strong or eventual.
                         Cannot be used with a transaction.
:type read_consistency: str
:param transaction: the transaction to use, if any.
:type transaction: str
:return: the response body of the lookup request.
:rtype: dict