Bug report

Bug description:

When using the built-in dict() constructor on a pandas.DataFrameGroupBy object, Python raises the following error:

TypeError: 'str' object is not callable
This happens despite the following confirmations:

dict is <class 'type'> and not overwritten

df.groupby('security') yields valid (str, DataFrame) pairs

{k: v for k, v in df.groupby(...)} works as expected

dict([('a', 1), ('b', 2)]) works as expected

Error persists even in fresh Poetry virtual environments and minimal isolated scripts

import pandas as pd

df = pd.DataFrame({
    'security': ['A', 'B'],
    'price': [1, 2]
})

print(dict(df.groupby('security')))

Expected output:

{
    'A': pd.DataFrame(...),
    'B': pd.DataFrame(...)
}

Actual output:
TypeError: 'str' object is not callable

Additional Notes

• No local or global shadowing of dict
• Running type(dict) returns <class 'type'>
• Running dict is builtins.dict returns True
• Minimal reproduction still fails with same error
• Appears to be interpreter-level misinterpretation of built-in symbol

I’ve run integrity checks, deleted caches, and rebuilt environments—all to no avail. Let me know if I can help isolate it further or dig into Python internals!

CPython versions tested on:

3.12

Operating systems tested on:

Linux