Hacky way to convert Zarr 2 to Zarr3

import zarr
def convert_attrs(z2,z3):
   z3.attrs.update(z2.attrs.asdict())

def convert_variable(v2,z3):
    compressors = zarr.codecs.BloscCodec(cname=v2.compressor.cname, clevel=v2.compressor.clevel, shuffle=zarr.codecs.BloscShuffle.shuffle.from_int(v2.compressor.shuffle),blocksize=v2.compressor.blocksize)
    v3 = z3.create_array(
         name=v2.name,
         shape=v2.shape,
         dtype=v2.dtype,
         compressors=compressors,
         chunks=v2.chunks,
         shards=v2.shards,
         order=v2.order,
         fill_value=v2.fill_value,
         dimension_names=v2.attrs.get('_ARRAY_DIMENSIONS'),
         overwrite=True
        )
    v3[:]=v2[:]
    convert_attrs(v2,v3)

def convert_groups(g2,g3):
    convert_attrs(g2,g3)
    for vname,v2 in g2.arrays():
            convert_variable(v2,g3)
    for g2 in g2.groups():
            convert_groups(g2,g3)

def convert_zarr(z2,z3):
    convert_groups(z2,z3)
    zarr.consolidate_metadata(z3.store)


if __name__ == '__main__':
    import sys
    if not len(sys.argv) in (2,3):
        print('Usage: {} <input.zarr> [<output.zarr>]'.format(sys.argv[0]))
        sys.exit(1)
    
    input_zarr = sys.argv[1]
    output_zarr = sys.argv[2] if len(sys.argv) == 3 else input_zarr + '3'
    z2 = zarr.open(input_zarr,mode='r')
    z3 = zarr.open(output_zarr,mode='w')
    convert_zarr(z2,z3)