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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 append_field(self, path, name, value):
 """ Appends the field to the container at the specified path. :param path: str or Path instance :param name: :type name: str :param value: :type value: str """

        path = make_path(path)
        container = self.get_container(path)
        current = container._values.get(name, None)
        if current is None:
            container._values[name] = value
        elif isinstance(current, ValueTree):
            raise TypeError()
        elif isinstance(current, list):
            container._values[name] = current + [value]
        else:
            container._values[name] = [current, value]