def openmm_read_statistics_file(statistics_file_name):
    """
    Read the statistics file produced by the plugin (backend) of
    SEEKR2 and extract transition statistics and times.

    Parameters
    ----------
    statistics_file_name : string
        The name of the openmmvt output file to read for extracting
        transition statistics

    Returns
    -------
    N_i_j_alpha_dict : dict
        dictionary of counts of transitions within cell alpha 
        between boundaries i and j.
        
    R_i_alpha_dict : dict
        dictionary of transition incubation times spent before 
        touching surface i
    
    N_alpha_beta_dict : dict
        dictionary array of counts that a transition between 
        cell alpha and beta
        
    T_alpha : float
        Total time spent within this cell.
    """
    raise Exception("Statistics needed for error analysis are not yet "\
                    "extracted in this function.")
    N_i_j_alpha_dict = defaultdict(int)
    R_i_alpha_dict = defaultdict(float)
    N_alpha_beta_dict = defaultdict(int)
    T_alpha = 0.0
    with open(statistics_file_name, 'r') as output_file:
        for line in output_file:
            linesplit = line.strip().split(' ')
            if line.startswith("N_alpha_"):
                keysplit = linesplit[0].split('_')
                dest_boundary = int(keysplit[2].strip(':'))
                value = int(linesplit[1])
                N_alpha_beta_dict[dest_boundary] += value
                
            elif line.startswith("N_"):
                keysplit = linesplit[0].split('_')
                src_boundary = int(keysplit[1])
                dest_boundary = int(keysplit[2])
                if src_boundary == dest_boundary:
                    continue
                value = int(linesplit[1])
                N_i_j_alpha_dict[(src_boundary, dest_boundary)] += value
                
            elif line.startswith("R_"):
                keysplit = linesplit[0].split('_')
                src_boundary = int(keysplit[1])
                value = float(linesplit[1])
                R_i_alpha_dict[src_boundary] += value
                
            elif line.startswith("T_alpha"):
                value = float(linesplit[1])
                T_alpha = value
                
            else:
                raise Exception("Unexpected line: %s in file %s" % \
                                (line, statistics_file_name))
            
    return N_i_j_alpha_dict, R_i_alpha_dict, N_alpha_beta_dict, T_alpha