…calling it an operator here is confusing. See https://docs.python.org/3/reference/lexical_analysis.html#operators and https://docs.python.org/3/faq/programming.html#id22.
single: , (comma)
Note that tuples are not formed by the parentheses, but rather by use of the
-comma operator. The exception is the empty tuple, for which parentheses *are*
+comma. The exception is the empty tuple, for which parentheses *are*
required --- allowing unparenthesized "nothing" in expressions would cause
ambiguities and allow common typos to pass uncaught.