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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 _updateKW(image, filename, exten, skyKW, Value):
 """update the header with the kw,value"""

    # Update the value in memory
    image.header[skyKW] = Value

    # Now update the value on disk
    if isinstance(exten,tuple):
        strexten = '[%s,%s]'%(exten[0],str(exten[1]))
    else:
        strexten = '[%s]'%(exten)
    log.info('Updating keyword %s in %s' % (skyKW, filename + strexten))
    fobj = fileutil.openImage(filename, mode='update', memmap=False)
    fobj[exten].header[skyKW] = (Value, 'Sky value computed by AstroDrizzle')
    fobj.close()