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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_OID_field(fs):
 """returns a featureset's object id field"""

    if arcpyFound == False:
        raise Exception("ArcPy is required to use this function")
    desc = arcpy.Describe(fs)
    if desc.hasOID:
        return desc.OIDFieldName
    return None