string representation of dictionary without quotes in values

Question

I am trying to create a string that can be evaluated to a dictionary such as:

'{"key1": val1, "key2": val2}'

I first tried:

str({key: "val%d" % i for i, key in enumerate(args)})

This mostly works except instead of val1 I get 'val1' . I might be able to do something with a for loop, but that felt awkward. Is there a better way of doing this?

Unfortunately I can't just pickle the dictionary, it needs to be a valid Python dictionary.

Answer 1

Not pretty, but accomplishes what you're looking for:

args = ["key1", "key2"]

your_attempt = str({key: "val%d" % i for i, key in enumerate(args)})
# outputs: "{'key2': 'val1', 'key1': 'val0'}"

your_attempt.replace("': '","': ").replace("', '",", '").replace("'}","}")
# outputs: "{'key2': val1, 'key1': val0}"

Answer 2

You could use eval() if this is what you are after:

val1 = "one"
val2 = "two"
test = '{"key1": val1, "key2": val2}'
test_dict = eval(test)
print(test_dict)
# {'key1': 'one', 'key2': 'two'}

Answer 3

For the sake of standardization, I would suggest using the builtin json library to encode and decode your info strings.

>>> json.dumps(['foo', {'bar': ('baz', None, 1.0, 2)}])
'["foo", {"bar": ["baz", null, 1.0, 2]}]'

>>> json.loads('["foo", {"bar":["baz", null, 1.0, 2]}]')
['foo', {'bar': ['baz', None, 1.0, 2]}]

The json module plays nice with request, pickle, etc. and can help you avoid headache and mistakes by implementing the formatting protocols for you.