UnboundLocalError at / local variable 'key' referenced before assignment

Question

here is my code i am facing this error i am not able to find the error fix the error shoow

def get_key(res_by):
    if res_by == '#1':
        key = 'transaction_id'
    elif res_by == '#2':
        key = 'created'
    return key
def get_chart(chart_type, data, results_by, **kwargs):
        plt.switch_backend('AGG')
        fig = plt.figure(figsize=(10,4))
        key = get_key(results_by)

thats the code

What if `res_by` isn't #1 or #2? – Loocid May 13 '21 at 05:25 — Loocid, May 13 '21 at 05:25
Both conditions didn't match, `key` is not set. – Klaus D. May 13 '21 at 05:25 — Klaus D., May 13 '21 at 05:25

score 0 · Answer 1 · answered May 13 '21 at 05:25

The problem is that in case both conditions fail, key is not assigned any value, but you return key. You thus need to specify a value in the else case:

def get_key(res_by):
    if res_by == '#1':
        key = 'transaction_id'
    elif res_by == '#2':
        key = 'created'
    else:
        key = something  # &leftarrow; specify a value if the two conditions fail
    return key

score 0 · Accepted Answer · answered May 13 '21 at 05:25

0

What if res_by is not #1 or #2? It wont be defined. Try this.

def get_key(res_by):
    if res_by == '#1':
        key = 'transaction_id'
    elif res_by == '#2':
        key = 'created'
    else:
        key = None
    return key

answered May 13 '21 at 05:25

Buddy Bob

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UnboundLocalError at / local variable 'key' referenced before assignment

2 Answers2