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: fiff_copy_tree.m
    path of file: ./repos/malini/Codes/deconvolution - model/spm8/external/mne
    
    the code of the file until where you have to start completion: function fiff_copy_tree(fidin, in_id, nodes, fidout)
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%    fiff_copy_tree(fidin, in_id, nodes, fidout)
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%    Copies directory subtrees from fidin to fidout
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%   Author : Matti Hamalainen, MGH Martinos Center
%   License : BSD 3-clause
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%    Revision 1.2  2009/04/01 21:25:50  msh
%    Fixed problems with fiff nodes with no tags in them
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%    Revision 1.1  2009/03/30 11:37:37  msh
%    Added copying of measurement info blocks from the original like in mne_browse_raw
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function fiff_copy_tree(fidin, in_id, nodes, fidout)
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%    fiff_copy_tree(fidin, in_id, nodes, fidout)
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%    Copies directory subtrees from fidin to fidout
%

%
%   Author : Matti Hamalainen, MGH Martinos Center
%   License : BSD 3-clause
%
%    Revision 1.2  2009/04/01 21:25:50  msh
%    Fixed problems with fiff nodes with no tags in them
%
%    Revision 1.1  2009/03/30 11:37:37  msh
%    Added copying of measurement info blocks from the original like in mne_browse_raw
%
%

me = 'MNE:fiff_copy_tree';

global FIFF;
if isempty(FIFF)
    FIFF = fiff_define_constants();
end