pytz question: GMT vs. UTC topic

According ato the pytz doc (http://pytz.sourceforge.net/):

"‘UTC’ is Universal Time, also known as Greenwich Mean Timeor GMT in
the United Kingdom."

If they are equal, why don't timezone objects created from those two
strings compare equal?

>>> pytz.timezone("UTC") == pytz.timezone("GMT")
False

(I'm revealing my complete ignorance of timezone manipulation by
asking this question.)

Thx,

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