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: process_input.m
    path of file: ./repos/automagic/gui/ratingGUI_utils
    
    the code of the file until where you have to start completion: function process_input(y, handles)
%process_intput Save the selected channel to the interpolation list and 

    
function process_input(y, handles)
%process_intput Save the selected channel to the interpolation list and 
%draw a line to mark it on the plot
%   handles  structure with handles of the gui
%   y        the y coordinate of the selected point

block = handles.project.getCurrentBlock();
list = block.tobeInterpolated;
y = int64(y);
if( ismember(y, list ) )
    error('No way the callback function is called here !')
else
    list = [list y];
    axe = handles.axes;
    axes(axe);
    draw_line(y, handles.project.maxX, handles, 'b', axe);
end