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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 add_filepath(self, manifest, filepath, fullpath, copy=False):
 """ Wrapper to the add_filepath function in PayuManifest. Prevents outside code from directly calling anything in PayuManifest. """

        filepath = os.path.normpath(filepath)
        if self.manifests[manifest].add_filepath(filepath, fullpath, copy):
            # Only link if filepath was added
            self.manifests[manifest].make_link(filepath)