Fix RecursionError in Item class

[saurbhc]

Problem

Printing the Item class raises RecursionError

from darwin.future.meta.client import Client

dataset = client.team.datasets.collect()[-1]
print(dataset.items.where().collect())

Traceback (most recent call last):
  File "t4.py", line 15, in <module>
    raise SystemExit(main())
  File "t4.py", line 8, in main
    print(dataset.items.where().collect())
  File "/Users/saurabhchopra/github/v7labs/darwin-py/darwin/future/meta/objects/base.py", line 50, in __repr__
    return str(self)
  File "/Users/saurabhchopra/github/v7labs/darwin-py/darwin/future/meta/objects/base.py", line 50, in __repr__
    return str(self)
  File "/Users/saurabhchopra/github/v7labs/darwin-py/darwin/future/meta/objects/base.py", line 50, in __repr__
    return str(self)
  [Previous line repeated 329 more times]
RecursionError: maximum recursion depth exceeded while getting the str of an object

Solution

Implement the missing __str__ method in Item class, which solves the issue.

Changelog

Fix RecursionError while printing an Item class.

[Nathanjp91]

Interested to understand why that causes a recursion error, and if it's general to all inherited meta objects, seeking to fix that (or enforce str as an abstractmethod), but good to approve this small fix.

[saurbhc]

Interested to understand why that causes a recursion error

From what I could see, it may be coming from the Base class -> __repr__ method [link] which was calling the str implementation - as there was no __str__ defined in Item class, it re-tried in a loop calling itself in recursion?

[Nathanjp91]

Interested to understand why that causes a recursion error

From what I could see, it may be coming from the Base class -> __repr__ method [link] which was calling the str implementation - as there was no __str__ defined in Item class, it re-tried in a loop calling itself in recursion?

Can you add in a default implementation to __str__ of that Base class for this PR, just print the underlying element it manages