in pybulletX/helper.py [0:0]
def flatten_nested_dict(d, parent_key="", sep="."):
items = []
for k, v in d.items():
new_key = parent_key + sep + k if parent_key else k
if isinstance(v, collections.abc.Mapping):
items.extend(flatten_nested_dict(v, new_key, sep=sep).items())
else:
items.append((new_key, v))
return dict(items)