<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def retrieve_from_cache(self):
 """Try to retrieve the node's content from a cache This method is called from multiple threads in a parallel build, so only do thread safe stuff here. Do thread unsafe stuff in built(). Returns true if the node was successfully retrieved. """

        if self.nocache:
            return None
        if not self.is_derived():
            return None
        return self.get_build_env().get_CacheDir().retrieve(self)