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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 get_fwhm_tag(expnum, ccd, prefix=None, version='p'):
 """ Get the FWHM from the VOSpace annotation. @param expnum: @param ccd: @param prefix: @param version: @return: """

    uri = get_uri(expnum, ccd, version, ext='fwhm', prefix=prefix)
    if uri not in fwhm:
        key = "fwhm_{:1s}{:02d}".format(version, int(ccd))
        fwhm[uri] = get_tag(expnum, key)
    return fwhm[uri]