Change power levels of room

how to change powerlevels.events_default in iOS?

in android we do this:

PowerLevels powerLevels = mRoom.getState().getPowerLevels().deepCopy();
powerLevels.events_default = 50;

mRoom.getDataHandler().getDataRetriever().getRoomsRestClient().updatePowerLevels(mRoom.getRoomId(), powerLevels, new ApiCallback() {
@Override
public void onSuccess(final Void info) {
if (null != getActivity()) {
getActivity().runOnUiThread(new Runnable() {
@Override
public void run() {
//code
}
});
}
}

private void onError(final String errorMessage) {
if (null != getActivity()) {
getActivity().runOnUiThread(new Runnable() {
@Override
public void run() {
hideLoadingView(true);
Toast.makeText(getActivity(), errorMessage, Toast.LENGTH_SHORT).show();
}
});
}
}

@Override
public void onNetworkError(Exception e) {
onError(e.getLocalizedMessage());
}

@Override
public void onMatrixError(MatrixError e) {
onError(e.getLocalizedMessage());
}

@Override
public void onUnexpectedError(Exception e) {
onError(e.getLocalizedMessage());
}
});

The issue provides an Android example using PowerLevels and updatePowerLevels, but names no iOS file, test, or entry point. Start by locating the iOS room state and power-level update flow, then determine how events_default can be changed on iOS. Done means an iOS-supported way to change that power level, with corresponding verification.

Written by the indexing model from the issue text.