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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 only_on_master(function):
 """Decorator that raises SoCoSlaveException on master call on slave."""

    @wraps(function)
    def inner_function(self, *args, **kwargs):
        """Master checking inner function."""
        if not self.is_coordinator:
            message = 'The method or property "{0}" can only be called/used '\
                'on the coordinator in a group'.format(function.__name__)
            raise SoCoSlaveException(message)
        return function(self, *args, **kwargs)
    return inner_function