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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 writeDrizKeywords(hdr,imgnum,drizdict):
 """ Write basic drizzle-related keywords out to image header as a record of the processing performed to create the image The dictionary 'drizdict' will contain the keywords and values to be written out to the header. """

    _keyprefix = 'D%03d'%imgnum

    for key in drizdict:
        val = drizdict[key]['value']
        if val is None: val = ""
        comment = drizdict[key]['comment']
        if comment is None: comment = ""
        hdr[_keyprefix+key] = (val, drizdict[key]['comment'])