[SMT-LIB] Assign value to a bitvector?

[Jun Koi]

hi,

In SMTLIB2, I want to assign a value to a bitvector variable, like below.

But Z3 reports error "invalid function application, sort mismatch on
argument at position 2 in line 3".

How can I fix this error?

Thanks.
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(set-logic QF_BV)
(declare-fun a () (_ BitVec 32))
(assert (= a #x0a))
(check-sat)