The mercantile module provides ul(xtile, ytile, zoom) and bounds(xtile, ytile, zoom) functions that respectively return the upper left corner and bounding longitudes and latitudes for XYZ tiles, a xy(lng, lat) function that returns spherical mercator x and y coordinates, a tile(lng, lat, zoom) function that returns the tile containing a given point, and quadkey conversion functions quadkey(xtile, ytile, zoom) and quadkey_to_tile(quadkey) for translating between quadkey and tile coordinates.