code: def encode_matrix_parameters(parameters):
      
      result = []
  
      for param in iter(sorted(parameters)):
          if isinstance(parameters[param], (list, tuple)):
              value = (';%s=' % (param)).join(parameters[param])
          else:
              value = parameters[param]
  
          result.append("%s=%s" % (param, value))
  
      return ';'.join(result)
docs: Performs encoding of url matrix parameters from dictionary to
      a string.
      See http://www.w3.org/DesignIssues/MatrixURIs.html for specs.