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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 adjust_properties (self, prop_set):
 """ For all virtual targets for the same dependency graph as self, i.e. which belong to the same main target, add their directories to include path. """

        assert isinstance(prop_set, property_set.PropertySet)
        s = self.targets () [0].creating_subvariant ()

        return prop_set.add_raw (s.implicit_includes ('include', 'H'))