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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 same_col(c):
 """Return True if all Mentions in the given candidate are from the same Col. :param c: The candidate whose Mentions are being compared :rtype: boolean """

    return same_table(c) and all(
        is_col_aligned(_to_span(c[i]).sentence, _to_span(c[0]).sentence)
        for i in range(len(c))
    )