Implementation of str.partition() with tuples

[harshsingh-24]

• Functionality: Split the string at the first occurrence of separator, and return a 3-tuple containing the part before the separator, the separator itself, and the part after the separator. If the separator is not found, return a 3-tuple containing the string itself, followed by two empty strings.
• Base Cases: If either string or separator is empty, a ValueError is raised. The ValueError function needs to be refactored further.
• Added sufficient test cases for integration testing along with proper comments for understanding

PS: Had a nice experience with git merge and resolving conflicts 😀

[harshsingh-24]

LPython CI build is successful. Can you please review @Thirumalai-Shaktivel @czgdp1807 and @Smit-create?

[certik]

Otherwise I think this is fine.

[certik]

This looks good, left some more comments. Keep this current design, no classes. Just a little more refactoring based on my comments above.

[harshsingh-24]

Can you review @certik and @Thirumalai-Shaktivel @Smit-create @czgdp1807 ? I incorporated all the changes.

PS: This was a really good PR for me as I learnt a lot through this.

[harshsingh-24]

Should I refactor of all the other functions like endswith, capitalize in the same way as I did for this function? @certik

[harshsingh-24]

Made the changes. @czgdp1807

[certik]

I think this looks good to me.

The history should be polished or squashed.

[harshsingh-24]

Why did the build fail? I submitted a successful build PR. @certik @czgdp1807

[certik]

@harshsingh-24 I think it failed due to #1645 (comment).