<s> import os <EOL> from . encoding import decode_from_system as decode , encode_to_system as encode <EOL> def get_env_var ( name , default = None ) : <EOL> try : <EOL> value = os . environ [ encode ( name ) ] <EOL> except KeyError : <EOL> return default <EOL> else : <EOL> return decode ( value ) <EOL> def set_env_var ( name , value ) : <EOL> os . environ [ encode ( name ) ] = encode ( value ) <EOL> def del_env_var ( name ) : <EOL> value = get_env_var ( name ) <EOL> if value is not None : <EOL> del os . environ [ encode ( name ) ] <EOL> return value <EOL> def get_env_vars ( upper = os . sep != '<STR_LIT:/>' ) : <EOL> return dict ( ( name if not upper else name . upper ( ) , get_env_var ( name ) ) <EOL> for name in ( decode ( name ) for name in os . environ ) ) </s>
