type RelayURL = Text

data Tag
    = ETag (EventId, RelayURL)
    | PTag (XOnlyPubKey, RelayURL)
    deriving (Eq, Show)

-- note: I have FromJSON for EventId and XOnlyPubKey already, they are hex-encoded in the json value

-- the json array looks like this:
-- [ "e", "063df25d22738a838cbbdc3dee470e0c58284954", "http://www.google.com"] -- for E-Tag
-- [ "p", "063df25d22738a838cbbdc3dee470e0c58284954", "http://www.gmail.com"] -- for P-Tag