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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 _combine_attribute(attr_1, attr_2, len_1, len_2):
 """ Helper function to combine trajectory properties such as site_properties or lattice """

        if isinstance(attr_1, list) or isinstance(attr_2, list):
            attribute = np.concatenate((attr_1, attr_2), axis=0)
            attribute_changes = True
        else:
            if isinstance(attr_1, list) and isinstance(attr_2, list) and np.allclose(attr_1, attr_2):
                attribute = attr_1
                attribute_changes = False
            else:
                attribute = [attr_1.copy()] * len_1 if type(attr_1) != list else attr_1.copy()
                attribute.extend([attr_2.copy()] * len_2 if type(attr_2 != list) else attr_2.copy())
                attribute_changes = True
        return attribute, attribute_changes