Combination of coins to achieve a total

ways.py

"""
From: https://breadth.substack.com/p/what-the-hell-is-a-deno
In Australia, we have the following coins:

5¢ 10¢ 20¢ 50¢ $1 and $2 coins.

One way of making up $3 is by:

$1 + 50¢ + 50¢ + 50¢ + 20¢ + 20¢ + 10¢

What is the total number of ways you can create $3 out of the 6 above listed coins?
"""

from collections import Counter

combinations = []

def ways(sorted_coins, target, frm=0, cnt=Counter()):
  global combinations
  if target == 0:
    for c in combinations:
      if c == cnt: return 0
    combinations.append(cnt)
    return 1
  elif target < 0 or frm >= len(sorted_coins):
    return 0

  return ways(sorted_coins, round(target-sorted_coins[frm], 2), frm, cnt + Counter({sorted_coins[frm]:1})) + ways(sorted_coins, target, frm+1, cnt+Counter())

def main():
  coins = [0.05, 0.1, 0.2, 0.5, 1, 2]
  target = 3
  sorted_coins = sorted(coins, reverse=True)
  frm = 0
  while sorted_coins[frm] > target:
    frm += 1
    if frm == len(sorted_coins):
      raise ValueError("Amount is not possible!")
  print(ways(sorted_coins, target, frm))
  #print(combinations)

if __name__ == "__main__":
  main()