What's the best way to read pd dataframe from local in Python? or How do I read pd dataframe from loc

For JSON, `pd.read_json()` is fine, but if it’s nested, try `json_normalize()` to flatten it first.

Also, if you’re reading pd dataframe from local files repeatedly, cache it!

`df.to_pickle()` + `pd.read_pickle()` is faster for re-reading the same data later.

Just don’t use pickle for long-term storage—it’s not version-stable.