How does one modify a dataframe with a callback? [former: circular import errors]

I think the payload is just too big for dcc.Store. Even with just one input and two outputs, load time is around 1 full minute.

Rows are 250k. [ specific error: Failed to execute 'setItem' on 'Storage': Setting the value of 'mdstore' exceeded the quota. ]

Does anyone have any links on storing data locally in cache? As mentioned here.

Any help appreciated. Thanks!