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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 list(self, path, filename=None, start=None, stop=None, recursive=False, directories=False):
 """ List objects specified by path. Returns sorted list of 'gs://' or 's3n://' URIs. """

        storageScheme, keys = self.getkeys(
            path, filename=filename, directories=directories, recursive=recursive)
        keys = [storageScheme + ":///" + key.bucket.name + "/" + key.name for key in keys]
        keys.sort()
        keys = select(keys, start, stop)
        return keys