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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def tile_exists(bounds, tile_z, tile_x, tile_y):
 """ Check if a mercatile tile is inside a given bounds. Attributes bounds : list WGS84 bounds (left, bottom, right, top). x : int Mercator tile Y index. y : int Mercator tile Y index. z : int Mercator tile ZOOM level. Returns ------- out : boolean if True, the z-x-y mercator tile in inside the bounds. """

    mintile = mercantile.tile(bounds[0], bounds[3], tile_z)
    maxtile = mercantile.tile(bounds[2], bounds[1], tile_z)

    return (
        (tile_x <= maxtile.x + 1)
        and (tile_x >= mintile.x)
        and (tile_y <= maxtile.y + 1)
        and (tile_y >= mintile.y)
    )