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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 arg_to_array(func):
 """ Decorator to convert argument to array. Parameters func : function The function to decorate. Returns ------- func : function The decorated function. """

    def fn(self, arg, *args, **kwargs):
        """Function

        Parameters
        ----------
        arg : array-like
            Argument to convert.
        *args : tuple
            Arguments.
        **kwargs : dict
            Keyword arguments.

        Returns
        -------
        value : object
            The return value of the function.
        """
        return func(self, np.array(arg), *args, **kwargs)
    return fn