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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 version(self):
 """ Compute the version identifier for this functional node using the func code and local names. Optionally, also allow closed-over variable values to affect the version number when closure_fingerprint is specified """

        try:
            f = self.func.__call__.__code__
        except AttributeError:
            f = self.func.__code__

        h = md5()
        h.update(f.co_code)
        h.update(str(f.co_names).encode())

        try:
            closure = self.func.__closure__
        except AttributeError:
            return h.hexdigest()

        if closure is None or self.closure_fingerprint is None:
            return h.hexdigest()

        d = dict(
            (name, cell.cell_contents)
            for name, cell in zip(f.co_freevars, closure))
        h.update(self.closure_fingerprint(d).encode())

        return h.hexdigest()