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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 timestamp(self, name="<block>"):
 """Returns a context manager for timestamping a block of code."""

        # Make a fake function
        func = lambda x: x
        func.__module__ = ""
        func.__name__ = name
        self.add_function(func)
        timestamps = []
        self.functions[func].append(timestamps)
        # A new object is required each time, since there can be several
        # nested context managers.
        return _TimeStamperCM(timestamps)