Function Z3_ast_vector_get 

pub unsafe extern "C" fn Z3_ast_vector_get(
    c: Z3_context,
    v: Z3_ast_vector,
    i: c_uint,
) -> Option<Z3_ast>

Return the AST at position i in the AST vector v.

Preconditions:

• i < Z3_ast_vector_size(c, v)