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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def add_preference(hdf5_file, preference):
 """Assign the value 'preference' to the diagonal entries of the matrix of similarities stored in the HDF5 data structure at 'hdf5_file'. """


    Worker.hdf5_lock.acquire()
    
    with tables.open_file(hdf5_file, 'r+') as fileh:
        S = fileh.root.aff_prop_group.similarities
        diag_ind = np.diag_indices(S.nrows)
        S[diag_ind] = preference
        
    Worker.hdf5_lock.release()