Google Colab

The file has been corrupted or is not a valid notebook file.
SyntaxError: Expected property name or '}' in JSON at position 2 (line 2 column 2)
CustomError: SyntaxError: Expected property name or '}' in JSON at position 2 (line 2 column 2)
    at new pM (https://ssl.gstatic.com/colaboratory-static/common/52ab59d64d72e779f904e6e0df6356b0/external_binary.js:2445:164)
    at va.program_ (https://ssl.gstatic.com/colaboratory-static/common/52ab59d64d72e779f904e6e0df6356b0/external_binary.js:2428:514)
    at ya (https://ssl.gstatic.com/colaboratory-static/common/52ab59d64d72e779f904e6e0df6356b0/external_binary.js:16:57)
    at va.next_ (https://ssl.gstatic.com/colaboratory-static/common/52ab59d64d72e779f904e6e0df6356b0/external_binary.js:14:195)
    at kaa.next (https://ssl.gstatic.com/colaboratory-static/common/52ab59d64d72e779f904e6e0df6356b0/external_binary.js:17:48)
    at b (https://ssl.gstatic.com/colaboratory-static/common/52ab59d64d72e779f904e6e0df6356b0/external_binary.js:17:309)