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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 _join_results(self, results, coarse, join):
    '''
    Join a list of results. Supports both get and series.
    '''
    rval = OrderedDict()
    i_keys = set()
    for res in results:
      i_keys.update( res.keys() )
    for i_key in sorted(i_keys):
      if coarse:
        rval[i_key] = join( [res.get(i_key) for res in results] )
      else:
        rval[i_key] = OrderedDict()
        r_keys = set()
        for res in results:
          r_keys.update( res.get(i_key,{}).keys() )
        for r_key in sorted(r_keys):
          rval[i_key][r_key] = join( [res.get(i_key,{}).get(r_key) for res in results] )
    return rval