def suba(a, b, c, d=0, e=0):
    """Subtract numbers b and c from number a. Optionally also subtract 
    either or both of numbers d and e from the result.
    """
    print(f"Function `suba` called with arguments a={a} b={b} c={c}", end="")
    if d: print(f" d={d}", end="")
    if e: print(f" e={e}", end="")
    print()
    return a - b - c - d - e