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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 register_std(self):
        ''' Registers all the standard checkers in the given checker.

        If not present already, the standard checkers schema (STD_NAMESPACE) is
        added to the checker's namespace with an empty prefix.
        '''
        self._namespace.register(STD_NAMESPACE, '')
        for cond in _ALL_CHECKERS:
            self.register(cond, STD_NAMESPACE, _ALL_CHECKERS[cond])