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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 split_by_category(biom_cols, mapping, category_id):
 """ Split up the column data in a biom table by mapping category value. """

    columns = defaultdict(list)
    for i, col in enumerate(biom_cols):
        columns[mapping[col['id']][category_id]].append((i, col))

    return columns