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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 load_parent(self, location):
 """Loads parent of Jamfile at 'location'. Issues an error if nothing is found."""

        assert isinstance(location, basestring)
        found = b2.util.path.glob_in_parents(
            location, self.JAMROOT + self.JAMFILE)

        if not found:
            print "error: Could not find parent for project at '%s'" % location
            print "error: Did not find Jamfile.jam or Jamroot.jam in any parent directory."
            sys.exit(1)

        return self.load(os.path.dirname(found[0]))