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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 row_content_length(row):
    '''
    Returns the length of non-empty content in a given row.
    '''
    if not row:
        return 0
    try:
        return (index + 1 for index, cell in reversed(list(enumerate(row))) if not is_empty_cell(cell)).next()
    except StopIteration:
        return len(row)