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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 _parse_standard_flag(read_buffer, mask_length):
 """Construct standard flag, standard mask data from the file. Specifically working on Reader Requirements box. Parameters fptr : file object File object for JP2K file. mask_length : int Length of standard mask flag """

    # The mask length tells us the format string to use when unpacking
    # from the buffer read from file.
    mask_format = {1: 'B', 2: 'H', 4: 'I'}[mask_length]

    num_standard_flags, = struct.unpack_from('>H', read_buffer, offset=0)

    # Read in standard flags and standard masks.  Each standard flag should
    # be two bytes, but the standard mask flag is as long as specified by
    # the mask length.
    fmt = '>' + ('H' + mask_format) * num_standard_flags
    data = struct.unpack_from(fmt, read_buffer, offset=2)

    standard_flag = data[0:num_standard_flags * 2:2]
    standard_mask = data[1:num_standard_flags * 2:2]

    return standard_flag, standard_mask