इस notebook को लोड करते समय कोई गड़बड़ी हुई. पक्का करें कि फ़ाइल को ऐक्सेस किया जा सकता हो और फिर से कोशिश करें.

पक्का करें कि आपके पास इस notebook को GitHub में देखने की अनुमति है. साथ ही, Colab को GitHub API इस्तेमाल करने की अनुमति दें.

https://github.com/flutter/codelabs/blob/master/tfrs-flutter/step1/backend/retrieval/retrieval.ipynb 
Fetch for https://api.github.com/repos/flutter/codelabs/contents/tfrs-flutter/step1/backend/retrieval?per_page=100&ref=master failed: {"message":"No commit found for the ref master","documentation_url":"https://docs.github.com/v3/repos/contents/","status":"404"}
CustomError: Fetch for https://api.github.com/repos/flutter/codelabs/contents/tfrs-flutter/step1/backend/retrieval?per_page=100&ref=master failed: {"message":"No commit found for the ref master","documentation_url":"https://docs.github.com/v3/repos/contents/","status":"404"}
    at new TM (https://ssl.gstatic.com/colaboratory-static/common/02c113afb31f45e79f7afe7969b93943/external_binary_l10n__hi.js:2565:68)
    at wa.program_ (https://ssl.gstatic.com/colaboratory-static/common/02c113afb31f45e79f7afe7969b93943/external_binary_l10n__hi.js:2548:436)
    at za (https://ssl.gstatic.com/colaboratory-static/common/02c113afb31f45e79f7afe7969b93943/external_binary_l10n__hi.js:16:57)
    at wa.next_ (https://ssl.gstatic.com/colaboratory-static/common/02c113afb31f45e79f7afe7969b93943/external_binary_l10n__hi.js:14:195)
    at kaa.next (https://ssl.gstatic.com/colaboratory-static/common/02c113afb31f45e79f7afe7969b93943/external_binary_l10n__hi.js:17:48)
    at b (https://ssl.gstatic.com/colaboratory-static/common/02c113afb31f45e79f7afe7969b93943/external_binary_l10n__hi.js:17:309)
 GitHub से अनुमति दें