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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 is_retaincase(bunchdt, data, commdct, idfobject, fieldname):
 """test if case has to be retained for that field"""

    thiscommdct = getfieldcomm(bunchdt, data, commdct, idfobject, fieldname)
    return 'retaincase' in thiscommdct