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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def build(self, **kw):
 """Actually build the node. This is called by the Taskmaster after it's decided that the Node is out-of-date and must be rebuilt, and after the prepare() method has gotten everything, uh, prepared. This method is called from multiple threads in a parallel build, so only do thread safe stuff here. Do thread unsafe stuff in built(). """

        try:
            self.get_executor()(self, **kw)
        except SCons.Errors.BuildError as e:
            e.node = self
            raise