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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 elem_find(self, field, value):
 """ Return the indices of elements whose field first satisfies the given values ``value`` should be unique in self.field. This function does not check the uniqueness. :param field: name of the supplied field :param value: value of field of the elemtn to find :return: idx of the elements :rtype: list, int, float, str """

        if isinstance(value, (int, float, str)):
            value = [value]

        f = list(self.__dict__[field])
        uid = np.vectorize(f.index)(value)
        return self.get_idx(uid)