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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_standalone(self, jamfile_module, file):
 """Loads 'file' as standalone project that has no location associated with it. This is mostly useful for user-config.jam, which should be able to define targets, but although it has some location in filesystem, we do not want any build to happen in user's HOME, for example. The caller is required to never call this method twice on the same file. """

        assert isinstance(jamfile_module, basestring)
        assert isinstance(file, basestring)

        self.used_projects[jamfile_module] = []
        bjam.call("load", jamfile_module, file)
        self.load_used_projects(jamfile_module)