in src/chug/wds/filters.py [0:0]
def _map_v2(data, f, handler=wds.reraise_exception):
""" Map samples.
This function differs from wds.map, it only adds '__key__' back to sample if it exists.
"""
for sample in data:
try:
result = f(sample)
except Exception as exn:
if handler(exn):
continue
else:
break
if result is None:
continue
if isinstance(sample, dict) and isinstance(result, dict) and "__key__" in sample:
result["__key__"] = sample.get("__key__")
yield result