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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 write(self, path, data, offset, fh):
 # pragma: no cover """ This is a readonly filesystem right now """

        # print("write {}".format(path))
        with self.attr_lock:
            base = self.attr[path][BASE_KEY]
            staged = self.attr[path][STAGED_KEY]
            if not staged.closed:
                base.st_size += len(data)
                staged.write(data)
        return len(data)