def resolve_dependencies(nodes):
    """ Figure out which order the nodes in the graph can be executed
    in to satisfy all requirements. """
    done = set()
    while True:
        if len(done) == len(nodes):
            break
        for node in nodes:
            if node.name not in done:
                match = done.intersection(node.requires)
                if len(match) == len(node.requires):
                    done.add(node.name)
                    yield node
                    break
        else:
            raise ConfigException('Invalid requirements in pipeline!')
def resolve_dependencies ( nodes ) : done = set ( ) while True : if len ( done ) == len ( nodes ) : break for node in nodes : if node . name not in done : match = done . intersection ( node . requires ) if len ( match ) == len ( node . requires ) : done . add ( node . name ) yield node break else : raise ConfigException ( 'Invalid requirements in pipeline!' )
Figure out which order the nodes in the graph can be executed
    in to satisfy all requirements.