我在这段代码中做错了什么

Question

I'm trying to make a request and parse the current btc price..

my code

import requests
import json



r = requests.get('https://blockchain.info/ticker')

k = r.text


Rate = json.loads(k)


print(Rate["last"])

and the output is

Traceback (most recent call last):
  File "wifi2.py", line 14, in <module>
    print(Rate["last"])
KeyError: 'last'

how can i fix it? thanks

Answer 1

This is a sample entry from the URL you provided:

"USD" : {"15m" : 11237.41, "last" : 11237.41, "buy" : 11237.41, "sell" : 11237.41, "symbol" : "$"}

They Key is the shorthand for the currency, and it's value is another dictionary, such that:

'USD' -> {..., "last": 11237.41, ...}

To get the value of the last key of the inner dictionary, you need to do for example:

print(Rate["USD"]["last"])

This returns the dictionary associated with the first key, then the value associated with the last key of the inner dictionary.