I want to construct a regular expression such as a* b* c*, There is a function re.++ in z3 that can concatenate 3 regular expressions together so I can construct a* b* c* as below
(assert (str.in.re "aabbc" (re.++ (re.* (str.to.re "a")) (re.* (str.to.re "b")) (re.* (str.to.re "c")))))
(check-sat)
However, I can't find such concatenation function in z3py API in the website: https://z3prover.github.io/api/html/namespacez3py.html
So my question is how can I concatenate multiple regular expressions using z3py?