def __prefix_key(self, key):
<EOL>if self.prefix is None:<EOL><INDENT>return key<EOL><DEDENT>if key.startswith(self.prefix + "<STR_LIT:->"):<EOL><INDENT>return key<EOL><DEDENT>return "<STR_LIT>".format(self.prefix, key)<EOL>
This will add the prefix to the key if one exists on the store