def _use_prototype(self, spec, prototypes):
prototype = spec['<STR_LIT>']<EOL>del spec['<STR_LIT>']<EOL>for attr in prototype:<EOL><INDENT>if attr not in spec:<EOL><INDENT>spec[attr] = copy.deepcopy(prototype[attr])<EOL><DEDENT><DEDENT>return spec<EOL>
Populates the given spec with the values of it's declared prototype

Args:
    spec (dict): spec to update
    prototypes (dict): Configuration spec containing the prototypes

Returns:
    dict: updated spec