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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 build_row(row, left, center, right):
 """Combine single or multi-lined cells into a single row of list of lists including borders. Row must already be padded and extended so each cell has the same number of lines. Example return value: [ ['>', 'Left ', '|', 'Center', '|', 'Right', '<'], ['>', 'Cell1', '|', 'Cell2 ', '|', 'Cell3', '<'], ] :param iter row: List of cells for one row. :param str left: Left border. :param str center: Column separator. :param str right: Right border. :return: Yields other generators that yield strings. :rtype: iter """

    if not row or not row[0]:
        yield combine((), left, center, right)
        return
    for row_index in range(len(row[0])):
        yield combine((c[row_index] for c in row), left, center, right)