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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 _join_data_lines(lines, skip):
 """ Join all the data lines into a byte string """

    lines = list(map(str.strip, lines))
    blank_lines = count_header_blanks(lines, skip)
    body = lines[skip + blank_lines + 2:]
    return '\n'.join(body)