from yt.mods import *
from yt.analysis_modules.halo_merger_tree.api import *
from yt.analysis_modules.halo_finding.api import *

files = []
start = 0
finish = 34
for i in range(start, finish + 1):
    files.append('./RD%04d/RedshiftOutput%04d' % (i, i))

MergerTree(restart_files=files, dm_only=True,database='./halos.db')