使用 Python 改变字典理解中 10% 的值

Question

我在进行字典理解时遇到问题。 我之前做过列表推导式，认为它们很相似，但用{}代替。

我很确定我的random逻辑是合理的，但对于我想要的任务。

更新字典：

import random

DLM = '~'  # deliminator

programmatic_dict = {
  "brand~test": "Ford",
  "model~test": "Mustang",
  "year~test": "2019"
}
print(programmatic_dict)

programmatic_dict = {programmatic_dict[key]: val + DLM + key.rsplit(DLM, 1)[1] else val for key, val in programmatic_dict.items() if random.randint(0,9) == 9}
print(programmatic_dict)

错误：

Traceback (most recent call last):
  File "/usr/lib/python3.8/py_compile.py", line 144, in compile
    code = loader.source_to_code(source_bytes, dfile or file,
  File "<frozen importlib._bootstrap_external>", line 846, in source_to_code
  File "<frozen importlib._bootstrap>", line 219, in _call_with_frames_removed
  File "./prog.py", line 13
    programmatic_dict = {programmatic_dict[key]: val + DLM + key.rsplit(DLM, 1)[1] else val for key, val in programmatic_dict.items() if random.randint(0,2) == 2}
                                                                                   ^
SyntaxError: invalid syntax

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "<string>", line 1, in <module>
  File "/usr/lib/python3.8/py_compile.py", line 150, in compile
    raise py_exc
py_compile.PyCompileError:   File "./prog.py", line 13
    programmatic_dict = {programmatic_dict[key]: val + DLM + key.rsplit(DLM, 1)[1] else val for key, val in programmatic_dict.items() if random.randint(0,2) == 2}
                                                                                   ^
SyntaxError: invalid syntax

期望输出：

programmatic_dict = {
  "brand~test": "Ford",
  "model~test": "Mustang~test",  # subtag in key string, added randomly at 10% (unlikely)
  "year~test": "2019"
}

我的字典理解代码行哪里出错了？

请让我知道是否还有什么我可以添加到帖子中以帮助进一步澄清（因为我知道我想要完成的任务很奇怪）。

Answer 1

2 修订：

• 引用任何键作为key: ,
• else else val else 语句，在 90% 的时间里，我不希望我的价值发生任何变化。

programmatic_dict = {key: val + DLM + key.rsplit(DLM, 1)[1] if random.randint(0, 9) == 9 else val for key, val in programmatic_dict.items()}

文章Ctrl+F：《Python 字典理解 if else》