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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 path_constant(self, name, value):
 """Declare and set a project global constant, whose value is a path. The path is adjusted to be relative to the invocation directory. The given value path is taken to be either absolute, or relative to this project root."""

        assert is_iterable_typed(name, basestring)
        assert is_iterable_typed(value, basestring)
        if len(value) > 1:
            self.registry.manager.errors()("path constant should have one element")
        self.registry.current().add_constant(name[0], value, path=1)