In fact, Python just has a non-binary AST with regard to operators, i.e. the expression "a < b < c" is not parsed as CompOp([CompOp([a, b], <), c], <) but instead as CompOp([a, b, c], [<, <]). The same holds by the way for Boolean operators, "a and b and c" is represented as BoolOp([a, b, c], [and, and]). See https://docs.python.org/3/library/ast.html#abstract-grammar for details.
