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: inpaint_nans.m
    path of file: ./repos/2D_ALDIC/func
    
    the code of the file until where you have to start completion: function B=inpaint_nans(A,method)
% INPAINT_NANS: in-paints over nans in an array
% usage: B=INPAINT_NANS(A)          % default method
% usage: B=INPAINT_NANS(A,method)   % specify method used
%
% Solves approximation to one of several pdes to
% interpolate and extrapolate holes in an array
%
% arguments (input):
%   A - nxm array with some NaNs to be filled in
%
%   method - (OPTIONAL) scalar numeric flag - specifies
%       which approach (or physical metaphor to use
%       for the interpolation.) All methods are capable
%       of extrapolation, some are better than others.
%       There are also speed differences, as well as
%       accuracy
    
function
% ====================================================
% ====================================================
%      begin subfunctions
% ====================================================
function neighbors_list=identify_neighbors(n,m,nan_list,talks_to)
% identify_neighbors: identifies all the neighbors of
%   those nodes in nan_list, not including the nans
%   themselves
%
% arguments (input):
%  n,m - scalar - [n,m]=size(A), where A is the
%      array to be interpolated
%  nan_list - array - list of every nan element in A
%      nan_list(i,1) == linear index of i'th nan element
%      nan_list(i,2) == row index of i'th nan element
%      nan_list(i,3) == column index of i'th nan element
%  talks_to - px2 array - defines which nodes communicate
%      with each other, i.e., which nodes are neighbors.
%
%      talks_to(i,1) - defines the offset in the row
%                      dimension of a neighbor
%      talks_to(i,2) - defines the offset in the column
%                      dimension of a neighbor
%      
%      For example, talks_to = [-1 0;0 -1;1 0;0 1]
%      means that each node talks only to its immediate
%      neighbors horizontally and vertically.
% 
% arguments(output):
%  neighbors_list - array - list of all neighbors of
%      all the nodes in nan_list

if ~isempty(nan_list)
  % use the definition of a neighbor in talks_to
  nan_count=size(nan_list,1);
  talk_count=size(talks_to,1);
  
  nn=zeros(nan_count*talk_count,2);
  j=[1,nan_count];
  for i=1:talk_count
    nn(j(1):j(2),:)=nan_list(:,2:3) + ...
        repmat(talks_to(i,:),nan_count,1);
    j=j+nan_count;
  end