Update composite.py

[stijn76]

use a list object instead of range object for SolutionArray._indices, to continue using the append function with Python 3 (which has no longer an append function for range objects).

Changes proposed in this pull request

If applicable, fill in the issue number this pull request is fixing

Closes #1085

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Checklist

• The pull request includes a clear description of this code change
• Commit messages have short titles and reference relevant issues
• Build passes (scons build & scons test) and unit tests address code coverage
• Style & formatting of contributed code follows contributing guidelines
• The pull request is ready for review

[ischoegl]

@stijn76 ... thank you for submitting, and congratulations for your first PR! 🎉!

[decaluwe]

Now you can make your second PR: adding your name to the AUTHORS file. 😁

[ischoegl]

Now you can make your second PR: adding your name to the AUTHORS file. 😁

@decaluwe has a point! But it's not too late to add this to this PR as it's not merged yet. Also, feel free to check the tick boxes in the PR description.

[ischoegl]

@stijn76 ... I wanted to briefly follow up. What @decaluwe referred to is the AUTHORS file in the main folder of the repository (which is a list of code contributors in alphabetical order). Feel free to add yourself, add the change to this PR, and I can merge.

[stijn76]

@ischoegl and @decaluwe : Thank you for the invitation to add my name to the authors file! I’ll take better care next time, also to add more comments in the bullet list of the pull request. For now, I’m okay with this; feel free to merge as is.