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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 clean(inst):
 """Routine to return FPMU data cleaned to the specified level Parameters inst : (pysat.Instrument) Instrument class object, whose attribute clean_level is used to return the desired level of data selectivity. Returns -------- Void : (NoneType) data in inst is modified in-place. Notes -------- No cleaning currently available for FPMU """


    inst.data.replace(-999., np.nan, inplace=True) # Te
    inst.data.replace(-9.9999998e+30, np.nan, inplace=True) #Ni

    return None