@classmethod
def subcells(cls, n):
    cells = []
    for i in range(n, 0, (- 1)):
        cells += (['pyr'] * ((i ** 2) + ((i - 1) ** 2)))
        cells += (['tet'] * ((2 * i) * (i - 1)))
    return cells
@classmethod
def subcells(cls, n):
    cells = []
    for i in range(n, 0, (- 1)):
        cells += (['pyr'] * ((i ** 2) + ((i - 1) ** 2)))
        cells += (['tet'] * ((2 * i) * (i - 1)))
    return cells