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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_to_list(my_list, my_element):
 """Helper function to add new my_element to my_list based on its type. Add as new element if it's not a list, otherwise extend to the list if it's a list. It's also guarantee that all elements are unique :param my_list: A list :type my_list: list :param my_element: A new element :type my_element: str, list :returns: A list with unique element :rtype: list """

    if isinstance(my_element, list):
        for element in my_element:
            my_list = add_to_list(my_list, element)
    else:
        if my_element not in my_list:
            my_list.append(my_element)

    return my_list