complex_if.py

def max_num(num1, num2,num3 ):
  if num1>= num2 and num1>= num3:
    return num1
  elif num2>=num1 and num2>= num3:
    return num2
  else:
    return num3

num1 = input("Enter the first number")
print(max_num(3, 4, 5))