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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 has_src_builder(self):
 """Return whether this Node has a source builder or not. If this Node doesn't have an explicit source code builder, this is where we figure out, on the fly, if there's a transparent source code builder for it. Note that if we found a source builder, we also set the self.builder attribute, so that all of the methods that actually *build* this file don't have to do anything different. """

        try:
            scb = self.sbuilder
        except AttributeError:
            scb = self.sbuilder = self.find_src_builder()
        return scb is not None