Importing ABC directly from collections was deprecated and will be removed in Python 3.10

[tirkarthi]

Describe the bug

Importing ABC directly from collections was deprecated and will be removed in Python 3.10 . Use collections.abc instead.

To Reproduce

rethinkdb/ast.py
87:    elif isinstance(val, collections.Callable):
108:    elif isinstance(val, collections.Mapping):
115:    elif isinstance(val, collections.Iterable):

System info

• Python client version: 3.8

[tirkarthi]

I will raise a PR to Python 2 to 3 branch.

[gabor-boros]

Cloud gb this issue as it is resolved on the 2 to 3 branch