You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: fixvolume.m
    path of file: ./repos/spm12/external/fieldtrip/utilities/private
    
    the code of the file until where you have to start completion: function data = fixvolume(data)

% FIXVOLUME cleans up the volume data representation, removes old and obsoleted

    
function data = fixvolume(data)

% FIXVOLUME cleans up the volume data representation, removes old and obsoleted
% fields and ensures that it is consistent with the most recent code.
%
% Use as
%   output = fixvolume(input)
% where input is a structure representing volume data
%
% See also FT_CHECKDATA, FIXSOURCE

% remove the unwanted fields
if isfield(data, 'pos'),     data = rmfield(data, 'pos');     end