Does the US need to require a mental examination before people can run for President?

I'm asking this question because we can now see the consequences of not performing such an examination. Had such an examination been performed prior to this person's first election, we might not be facing the current situation. Perhaps if a mental examination had been performed prior to the first election of this person, we would not be in this situation at this time. Is a pre-election mental examination a good idea?

Does the US need to require a mental examination before people can run for President?
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