Parse math formulas in python and put parentheses around Mult/Div

main.py

from __future__ import print_function
import ast


def recurse(node):
    if isinstance(node, ast.BinOp):
        if isinstance(node.op, ast.Mult) or isinstance(node.op, ast.Div):
            print('(', end='')
        recurse(node.left)
        recurse(node.op)
        recurse(node.right)
        if isinstance(node.op, ast.Mult) or isinstance(node.op, ast.Div):
            print(')', end='')
    elif isinstance(node, ast.Add):
        print('+', end='')
    elif isinstance(node, ast.Sub):
        print('-', end='')
    elif isinstance(node, ast.Mult):
        print('*', end='')
    elif isinstance(node, ast.Div):
        print('/', end='')
    elif isinstance(node, ast.Num):
        print(node.n, end='')
    else:
        for child in ast.iter_child_nodes(node):
            recurse(child)


def search_expr(node):
    returns = []
    for child in ast.iter_child_nodes(node):
        if isinstance(child, ast.Expr):
            return child
        returns.append(search_expr(child))
    for ret in returns:
        if isinstance(ret, ast.Expr):
            return ret
    return None


formula = '3+7*8/2'

a = ast.parse(formula)

expr = search_expr(a)
if expr is not None:
    recurse(expr)

Legend Thankyou, just tested perfectly. I will trawl over it and see if I can learn more about it and not have to ask next time.
All part of my new COVID skills in python

Looking good! So nice to see that there are good things coming out of COVID :)