Update basic_graphs.py

[karthikeyansa]

missing return statement line no:223.

Describe your change:

• Add an algorithm?
• Fix a bug or typo in an existing algorithm?
• Documentation change?

Checklist:

• I have read CONTRIBUTING.md.
• This pull request is all my own work -- I have not plagiarized.
• I know that pull requests will not be merged if they fail the automated tests.
• This PR only changes one algorithm file. To ease review, please open separate PRs for separate algorithms.
• All new Python files are placed inside an existing directory.
• All filenames are in all lowercase characters with no spaces or dashes.
• All functions and variable names follow Python naming conventions.
• All function parameters and return values are annotated with Python type hints.
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[poyea]

Thank you for your PR. Why would this return a sum? Prim's algorithm should return a tree.
Also, this file has some other issues - no tests or references for algorithms. You may consider fixing some of those for functions in this file.

[itsvinayak]

@poyea is this seems ok
now it returns the map with the path values

[cclauss]

@poyea Please re-review.

[poyea]

Thank you for your pull request!🤩

[poyea]

@karthikeyansa @cclauss @itsvinayak I think we can add some test graphs to this file, as it is quite difficult to see the expected output. An input graph for prim should be of the form

{ "a" : [["d",1]], "b" : [["c",2], ["e",2]],"c" : [["a",1], ["b",2], ["d",3], ["e",2]],"d" : [["c",2]],"e" : [["c",1], ["b",3]],"f" : []}

However, Dictionary of edges underspecifies the requirement of this argument, though there is an input option for constructing the dictionary.