def get(self, key, default = None):
        """
        @type key: bytes
        @param key: The key to lookup

        @param default: The value to return if the given key does not exist

        @return: The value associated with C{key} or C{default} if not
        L{DirDBM.has_key(key)}
        """
        if key in self:
            return self[key]
        else:
            return default

        @type key: bytes
        @param key: The key to lookup

        @param default: The value to return if the given key does not exist

        @return: The value associated with C{key} or C{default} if not
        L{DirDBM.has_key(key)}
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/persisted/dirdbm.py