Module has no attribute "interchange"

[MarcoGorelli]

Describe the bug
A clear and concise description of what the bug is.

To Reproduce

1. Provide a minimal runnable pandas example that is not properly checked by the stubs.
2. Indicate which type checker you are using (mypy or pyright).
3. Show the error message received from that type checker while checking your example.

(.venv) marcogorelli@DESKTOP-U8OKFP3:~/tmp$ cat t.py
import pandas as pd

df = pd.DataFrame({'a': [1, 2, 3]})

res = pd.api.interchange.from_dataframe(df)
print(res)

(.venv) marcogorelli@DESKTOP-U8OKFP3:~/tmp$ mypy t.py
t.py:5: error: Module has no attribute "interchange"  [attr-defined]
Found 1 error in 1 file (checked 1 source file)
(.venv) marcogorelli@DESKTOP-U8OKFP3:~/tmp$ pip freeze | grep pandas
pandas==2.0.1
pandas-stubs==2.0.1.230501
(.venv) marcogorelli@DESKTOP-U8OKFP3:~/tmp$ pip freeze | grep mypy
mypy==1.3.0
mypy-extensions==1.0.0

Please complete the following information:

• OS: [e.g. Windows, Linux, MacOS] linux
• OS Version [e.g. 22]
• python version 3.10.6
• version of type checker mypy
• version of installed pandas-stubs 2.0.1.230501

Additional context
Add any other context about the problem here.

[Dr-Irv]

Need to add

    interchange as interchange,

to pandas-stubs/api/__init__.pyi

PR with tests welcome.