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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 find_spec(self, fullname, path, target=None):
 """ Claims modules that are under ipynb.fs """

        if fullname.startswith(self.package_prefix):
            for path in self._get_paths(fullname):
                if os.path.exists(path):
                    return ModuleSpec(
                        name=fullname,
                        loader=self.loader_class(fullname, path),
                        origin=path,
                        is_package=(path.endswith('__init__.ipynb') or path.endswith('__init__.py')),
                    )