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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 fetch(self, value_obj=None):
        ''' Fetch the next two values '''
        val = None
        try:
            val = next(self.__iterable)
        except StopIteration:
            return None
        if value_obj is None:
            value_obj = Value(value=val)
        else:
            value_obj.value = val
        return value_obj