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: ftcolors.m
    path of file: ./repos/fieldtrip/plotting/private
    
    the code of the file until where you have to start completion: function rgb = ftcolors(N)


    
function rgb = ftcolors(N)

% FTCOLORS returns an Nx3 rgb matrix with the
% colors of the fieldtrip logo at its extremes.
% Can be used as a colormap by FT_COLORMAP
%
% Use as:
%   rgb = ftcolors(N), or
%   rgb = ftcolors
%
% Without input arguments, N will be set to 64

if nargin==0
  N = 64;
end