Python标牌计费程序报错：无法确定颜色类型（Call与str类型不匹配）

我在做一个标牌费用计算的编程作业，代码运行结果符合预期（比如金字、8字符、松木材质的标牌最终能算出62美元），但每次测试都会触发错误提示：

Reason: Unable to determine color type. Type mismatch: Cannot replace Call with str.

我的代码 #

# Initialize variables here.
charge = 0
num_chars = 8
color = "gold"
wood_type = "oak"
minChars = 5
costChars = 4

# Charge for this sign.

# Number of characters.
print("The first five letters are included in the minimum charge, but each individual character afterwards is an additional 4$")
num_chars = int(input("Enter how many characters you will have on the sign: ")
if num_chars > minChars:
    charge = (num_chars - minChars) * costChars
# Color of characters.
color = input("Do you wan to pay 15$ additional for gold lettering or black and white: ")
if color == "gold":
    charge = charge + 15
elif color == "black and white":
    charge
# Type of wood.
wood_type = input("Do you wan to pay 20$ additional oak or pine: ")
if wood_type == "oak":
    charge = charge + 20
elif wood_type == "pine":
    charge
# Write assignment and if statements here as appropriate.

# Output Charge for this sign.
charge = charge + 35
print(f"The charge for this sign is ${charge:.2f}")

测试失败输出 #

Status: FAILED!
Check: 1
Test: Black and white, 5 letter, on pine (minimum charge).
Reason: Unable to determine color type. Type mismatch: Cannot replace Call with str.
Error : ValueError - Unable to determine color type. Type mismatch: Cannot replace Call with str.
Timestamp: 2024-04-27 20:20:03.443145

Status: FAILED!
Check: 2
Test: Gold leaf, 10 letter, on oak.
Reason: Unable to determine color type. Type mismatch: Cannot replace Call with str.
Error : ValueError - Unable to determine color type. Type mismatch: Cannot replace Call with str.
Timestamp: 2024-04-27 20:20:03.443463

Status: FAILED!
Check: 3
Test: Gold leaf, 8 letter, on pine.
Reason: Unable to determine color type. Type mismatch: Cannot replace Call with str.
Error : ValueError - Unable to determine color type. Type mismatch: Cannot replace Call with str.
Timestamp: 2024-04-27 20:20:03.443735

问题修复 #

1. 核心语法错误：num_chars = int(input("Enter how many characters you will have on the sign: ")) 这一行原代码少了一个闭合括号，导致Python解析代码时出现语法错误，后续的颜色判断逻辑因此失效，触发类型不匹配的报错。
2. 拼写错误修正：输入提示里的wan改为want，避免用户误解输入要求。
3. 无效代码清理：elif color == "black and white":和elif wood_type == "pine":下的单独charge语句无实际作用，可直接删除。
4. 输入健壮性优化（可选）：对用户输入做去空格和大小写转换，比如color = input(...).strip().lower()，避免因用户输入大小写或空格导致判断失败。

修复后的完整代码 #

# Initialize variables here.
charge = 0
num_chars = 8
color = "gold"
wood_type = "oak"
minChars = 5
costChars = 4

# Charge for this sign.

# Number of characters.
print("The first five letters are included in the minimum charge, but each individual character afterwards is an additional 4$")
num_chars = int(input("Enter how many characters you will have on the sign: "))
if num_chars > minChars:
    charge = (num_chars - minChars) * costChars
# Color of characters.
color = input("Do you want to pay 15$ additional for gold lettering or black and white: ").strip().lower()
if color == "gold":
    charge += 15
# Type of wood.
wood_type = input("Do you want to pay 20$ additional for oak or pine: ").strip().lower()
if wood_type == "oak":
    charge += 20
# Output Charge for this sign.
charge += 35
print(f"The charge for this sign is ${charge:.2f}")

内容的提问来源于stack exchange，提问作者liam ruddy