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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 size(self):
 """Return the total size in bytes of all the files handled by this instance of fsdb. Fsdb does not use auxiliary data structure, so this function could be expensive. Look at _iter_over_paths() functions for more details. """

        tot = 0
        for p in self.__iter__(overPath=True):
            tot += os.path.getsize(p)
        return tot