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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 walk(self):
 """Walk through commands."""

        yield self
        if self.has_arguments():
            for arg in self.args_definition:
                if not arg["name"] in self.arguments:
                    continue
                value = self.arguments[arg["name"]]
                if type(value) == list:
                    if self.__get_arg_type(arg["name"]) == ["testlist"]:
                        for t in value:
                            for node in t.walk():
                                yield node
                if isinstance(value, Command):
                    for node in value.walk():
                        yield node
        for ch in self.children:
            for node in ch.walk():
                yield node