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: get_number_of_buses.m
    path of file: ./repos/rapidPF/01_generator/auxfuns
    
    the code of the file until where you have to start completion: function N = get_number_of_buses(mpc)
% get_number_of_buses
%
%   `N = get_number_of_buses(mpc)`
%
%   _Get the number of buses in a case file_

    
function N = get_number_of_buses(mpc)
% get_number_of_buses
%
%   `N = get_number_of_buses(mpc)`
%
%   _Get the number of buses in a case file_
%
%   ## See also:
%   - [get_number_of_branches](get_number_of_branches.md)
%   - [get_number_of_connected_generators](get_number_of_connected_generators.md)
%   - [get_number_of_generators](get_number_of_generators.md)
    N = size(mpc.bus, 1);
    % check 1:N numbering
    assert(sum(1:N) == sum(mpc.bus(:,1)), 'This code assumse 1:N numbering in buses. Please check.')
end