def load_backend(backend_name):
try:<EOL><INDENT>if len(backend_name.split("<STR_LIT:.>")) > <NUM_LIT:1>:<EOL><INDENT>mod = import_module(backend_name)<EOL><DEDENT>else:<EOL><INDENT>mod = import_module("<STR_LIT>" % backend_name)<EOL><DEDENT>return mod<EOL><DEDENT>except ImportError:<EOL><INDENT>error_msg = "<STR_LIT>" % backend_name<EOL>raise ImportError(error_msg)<EOL><DEDENT>
load pool backend.