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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 make_instance(self, command):
 """Create and initialize an instance of a user-defined class. command must be a string in the form: (<instance-name> of <class-name> <slot-override>*) <slot-override> :== (<slot-name> <constant>*) Python equivalent of the CLIPS make-instance command. """

        ist = lib.EnvMakeInstance(self._env, command.encode())
        if ist == ffi.NULL:
            raise CLIPSError(self._env)

        return Instance(self._env, ist)