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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 set_pattern_actual_step(self, patternnumber, value):
 """Set the 'actual step' parameter for a given pattern. Args: * patternnumber (integer):
 0-7 * value (integer):
 0-7 """

        _checkPatternNumber(patternnumber)
        _checkStepNumber(value)
        
        address = _calculateRegisterAddress('actualstep', patternnumber)
        self.write_register(address, value, 0)