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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 remove_builder(cls, builder_name: str):
 """Remove a registered builder `builder_name`. No reason to use this except for tests. """

        cls.builders.pop(builder_name, None)
        for hook_spec in cls.hooks.values():
            hook_spec.pop(builder_name, None)