Syntax error in format string

[kenya-sk]

There appear to be syntax errors in several files where format strings are missing "{}", which results in the output not matching intended strings.

For example, this issue can be founded at line 67 in tensorflow_quantum/datasets/cluster_state.py.
In addition, I identified similar errors in approximately in other 10 files.

# Format error
raise TypeError('qubits must be a list or np.ndarray. Given: '.format(
    type(qubits)))

# Correct
raise TypeError('qubits must be a list or np.ndarray. Given: {}'.format(
    type(qubits)))

[kenya-sk]

If it seems like this needs to be addressed, I can thoroughly scan the repository's Python files and open a PR with proposed fixes.
Thank you.

[mhucka]

Thank you for your interest and for finding this. You're right, that does look like a mistake. In terms of fixing it, it would be better to switch away from using format altogether and use Python f-strings. If you'd be interested in doing a pull request for that, we'd definitely welcome it!

[kenya-sk]

Thank you for your response.
I agree to replace format string with f-strings. To maintain consistency, I will convert the entire codebase to f-strings, including those that are already working as intended, and create a pull request.

[mhucka]

Thanks!

I just realized something, and what I wrote before is not correct. A better software engineering practice is to separate formatting changes from actual bug fixes. What you pointed out initially in this issue was a bug, and so a better (albeit more time-consuming, unfortumately) procedure would be to make 2 PRs:

• First PR: Bug fixes, to add missing {} to format statements where appropriate (as you originally proposed).
• Second PR: Format changes – no functional changes or bug fixes, just converting format strings to f-strings.

My apologies for not thinking through it at first and responding too hastily.

If this is too much work and you'd rather just do a PR for #1, that's okay – in itself, that would be a welcome contribution!

(Incidentally, flynt may be useful for the second PR.)

[kenya-sk]

Thanks for the clarification, that makes sense now!

I'll follow that approach: first I'll open a PR just for the bug fixes, and then work on a separate PR to convert the formatting to f-strings.