JSONDecodeError: Expecting value: line 1 column 1 (char 0)

The error message "JSONDecodeError: Expecting value: line 1 column 1 (char 0)" typically occurs when you are trying to parse a string as JSON, but the string is not in a valid JSON format.

This error is raised by the json library when it encounters an unexpected character (char 0) at the beginning of the input string, it was expected a JSON value. It could happen due to:

  • The input string is empty.
  • The input string is not a valid JSON format, it may contain additional characters or syntax errors.
  • The input is not a string at all, but another data type such as an int, float or None.

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You can try the following to fix the issue:

  1. Make sure that the input you are providing is a valid JSON string.
  2. Check if there are any syntax errors in your JSON string, such as missing quotes or commas.
  3. Inspect the input to make sure it is a string and not an empty value, you can do that by adding a check for if not input_string: before trying to parse it.
  4. Ensure that the input is a string, json.loads can only work on strings.

If the error persists, it may be helpful to check the code where the input is being obtained, to see if it could be modified to always output a valid json string.

In German, the error message would look like this: "JSONDecodeError: Erwarte Wert: Zeile 1 Spalte 1 (Zeichen 0)"