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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 _events_with_diff_tag(talk, tag_array):
 """ Return the indices of the events with no tag in common as tag """

    event_categories = np.nonzero(tag_array[talk])[0]
    return np.nonzero(sum(tag_array.transpose()[event_categories]) == 0)[0]