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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 add_arg(self,arg, prepend=False):
 """Append an arg to the arg list"""


        self.args = [arg_.strip() for arg_ in self.args if arg_.strip()]

        if arg.title() not in self.args:
            if prepend:
                self.args = [arg.title()] + self.args
            else:
                self.args.append(arg.title())