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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 whichframes(fn, FrameIndReq, kineticsec, ut1req, startUTC, firstRawInd, lastRawInd, BytesPerImage, BytesPerFrame, verbose):
 ext = Path(fn).suffix # %% get file size fileSizeBytes = fn.stat().st_size if fileSizeBytes < BytesPerImage: raise ValueError( f'File size {fileSizeBytes} is smaller than a single image frame!') if ext == '.DMCdata' and fileSizeBytes % BytesPerFrame: logging.error( f"Looks like I am not reading this file correctly, with BPF: {BytesPerFrame:d}") if ext == '.DMCdata': nFrame = fileSizeBytes // BytesPerFrame print(f'{nFrame} frames, Bytes: {fileSizeBytes} in file {fn}') nFrameRaw = (lastRawInd - firstRawInd + 1) if nFrameRaw != nFrame: logging.warning( f'there may be missed frames: nFrameRaw {nFrameRaw} nFrame {nFrame}') else: nFrame = lastRawInd - firstRawInd + 1 allrawframe = arange(firstRawInd, lastRawInd + 1, 1, dtype=int64) print(f"first / last raw frame #'s: {firstRawInd} / {lastRawInd} ") # %% absolute time estimate ut1_unix_all = frame2ut1(startUTC, kineticsec, allrawframe) # %% setup frame indices """ if no requested frames were specified, read all frames. Otherwise, just return the requested frames Assignments have to be "int64", not just python "int". Windows python 2.7 64-bit on files >2.1GB, the bytes will wrap """

    FrameIndRel = ut12frame(ut1req,
                            arange(0, nFrame, 1, dtype=int64),
                            ut1_unix_all)

    # NOTE: no ut1req or problems with ut1req, canNOT use else, need to test len() in case index is [0] validly
    if FrameIndRel is None or len(FrameIndRel) == 0:
        FrameIndRel = req2frame(FrameIndReq, nFrame)

    badReqInd = (FrameIndRel > nFrame) | (FrameIndRel < 0)
# check if we requested frames beyond what the BigFN contains
    if badReqInd.any():
        # don't include frames in case of None
        raise ValueError(f'frames requested outside the times covered in {fn}')

    nFrameExtract = FrameIndRel.size  # to preallocate properly
    nBytesExtract = nFrameExtract * BytesPerFrame
    print(
        f'Extracted {nFrameExtract} frames from {fn} totaling {nBytesExtract/1e9:.2f} GB.')

    if nBytesExtract > 4e9:
        print(f'This will require {nBytesExtract/1e9:.2f} GB of RAM.')

    return FrameIndRel