#NEWLINE# def _get_string_to_sign( self , request , timestamp , payload_sha256 ) : #NEWLINE# #INDENT# canonical_request_sha256 = self . _get_canonical_request_sha256 ( request , timestamp ) #NEWLINE# return '\n' . join ( [ 'AWS4-HMAC-SHA256' , timestamp , self . _get_scope ( timestamp ) , canonical_request_sha256 ] )