quantlab.dataset.sharadar.permatickers.SeenSpan

class quantlab.dataset.sharadar.permatickers.SeenSpan(first, last, end)

Bases: object

One security under one ticker in the TICKERS history (raw_tier.fold_tickers_history).

first and last are the pull times (UTC) of the first and last snapshots holding the pair; end is the day before a snapshot after last first shows the security under another ticker or the ticker under another security (None: none has).