<s> import os <EOL> def get ( ) : <EOL> return dict ( os . environ ) <EOL> def set ( key , value ) : <EOL> if key is not None : <EOL> os . environ [ str ( key ) ] = str ( value ) <EOL> def get_key ( key , default_value = None ) : <EOL> if not key : <EOL> return default_value <EOL> key = str ( key ) <EOL> value = get ( ) . get ( key ) <EOL> if value is None : <EOL> value = default_value <EOL> return value </s>
