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I24UEJQLCH2SOXA4UHIYWTRDCHSOPU7AFTRUOTX7HZIAV4AZKYEQC
GHO6DWPILBBTL6CVZKERJBTFL3EY6ZT4YM4E5R4S6YPGVFKFHCVAC
SXEYMYF7P4RZMZ46WPL4IZUTSQ2ATBWYZX7QNVMS3SGOYXYOHAGQC
/// Delete a key and a value from a graph. Returns `true` if and only if `(k, v)` was in the graph.
|| p.is_empty()
|| (p.is_empty() && !e.flag().contains(EdgeFlags::PSEUDO))