ox2schematic alien_crawl1.vox 
2021-03-13 17:35:33,411 Vox input file: alien_crawl1.vox
2021-03-13 17:35:33,411 Schematic output file: alien_crawl1.schematic
2021-03-13 17:35:33,412 Material data not found
Traceback (most recent call last):
  File "/home/hellocatfood/.local/bin/vox2schematic", line 71, in <module>
    main()
  File "/home/hellocatfood/.local/bin/vox2schematic", line 62, in main
    voxels._blocks_memory.to_schematic(schematic_file)
  File "/home/hellocatfood/.local/lib/python3.8/site-packages/mcthings/blocks_memory.py", line 254, in to_schematic
    self.build_schematic().write_file(file_path)
  File "/home/hellocatfood/.local/lib/python3.8/site-packages/mcthings/blocks_memory.py", line 244, in build_schematic
    return self.to_nbt(init_pos, end_pos, self)
TypeError: to_nbt() takes 3 positional arguments but 4 were given