/work/projects/fmu-ensemble/src/fmu/ensemble/realization.py:837: FutureWarning: The frame.append method is deprecated and will be removed from pandas in a future version. Use pandas.concat instead.
returnedslice = returnedslice.append(filerow, ignore_index=True)
This line triggers a FutureWarning in Pandas 1.4.2:
https://github.com/equinor/fmu-ensemble/blob/11f2e9badac792437a1cf86ea2739768056c45aa/src/fmu/ensemble/realization.py#L836