Function Z3_get_quantifier_bound_name 

pub unsafe extern "C" fn Z3_get_quantifier_bound_name(
    c: Z3_context,
    a: Z3_ast,
    i: c_uint,
) -> Option<Z3_symbol>

Return symbol of the i’th bound variable.

Preconditions:

• Z3_get_ast_kind(a) == AstKind::Quantifier