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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 getadistus(data, commdct):
 """docstring for fname"""

    objkey = "ZoneHVAC:AirDistributionUnit".upper()
    objindex = data.dtls.index(objkey)
    objcomm = commdct[objindex]
    adistutypefield = "Air Terminal Object Type"
    ifield = getfieldindex(data, commdct, objkey, adistutypefield)
    adistus = objcomm[ifield]['key']
    return adistus