for L, H in intervals:
    print('\nprec = %d   (L,H) = (%d,%d)' % (prec, L, H))
print('prec = %d <= L-1 = %d : %s' % (prec, L - 1, prec <= L))
if prec <= L - 1:
    yield prec, L - 1
prec = H + 1
print('next prec = %d' % prec)
holes = list(gaps_between(table))
print() 
print('table =', table)
print('holes =', holes)
How to subtract one from every value in a tuple in Python?