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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 param_apropos(self, args):
        '''search parameter help for a keyword, list those parameters'''
        if len(args) == 0:
            print("Usage: param apropos keyword")
            return

        htree = self.param_help_tree()
        if htree is None:
            return

        contains = {}
        for keyword in args:
            for param in htree.keys():
                if str(htree[param]).find(keyword) != -1:
                    contains[param] = True
        for param in contains.keys():
            print("%s" % (param,))