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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 GetServices(self,filename):
 """Returns a list of service objects handling this file type"""

        objlist=[]
        for sobj in self.services:
            if sobj.KnowsFile(filename) :
                objlist.append(sobj)

        if len(objlist)==0:
            return None

        return objlist