Can Rattata be shiny in Pokemon GO?

At the end of the Season of Mischief in Pokemon GO, trainers can catch a bunch of shiny Pokemon, including Rattata.

Pokemon Go shiny list and shiny you can catch

First Helper Shiny Rattata : r/PokemonSleep

Shiny Rattata: Let's GO Eevee - (Shiny Living Dex 1/150)

Geek Shelf - ⚹Turtwig Community Day⚹ . Not too bad here, got myself 8 Turtwig shinies and also my first Alolan Rattata shiny too! . I think this was also my first

Pokemon 18019 Shiny Alolan Rattata Pokedex: Evolution, Moves, Location, Stats

Shiny Rattata/Raticate (Alola Form) 6IV - Pokemon Sun/Moon US/UM Let's Go

Shiny Rattata - Pokemon Go

Pokémon GO Shiny Party Hat Raticate – Trade 20.000 stardust (Read Describe) - PoGoFighter

Alola Rattata Is Now Appearing In Pokemon GO – NintendoSoup

Pokemon 6019 Shiny Rattata Lightning Pokedex: Evolution, Moves, Location, Stats