def convert_binom(binom):
    expr_top = convert_expr(binom.upper)
    expr_bot = convert_expr(binom.lower)
    return sympy.binomial(expr_top, expr_bot)
def convert_binom(binom):
    expr_top = convert_expr(binom.upper)
    expr_bot = convert_expr(binom.lower)
    return sympy.binomial(expr_top, expr_bot)