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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 removeTags(dom):
 """ Remove all tags from `dom` and obtain plaintext representation. Args: dom (str, obj, array):
 str, HTMLElement instance or array of elements. Returns: str: Plain string without tags. """

    # python 2 / 3 shill
    try:
        string_type = basestring
    except NameError:
        string_type = str

    # initialize stack with proper value (based on dom parameter)
    element_stack = None
    if type(dom) in [list, tuple]:
        element_stack = dom
    elif isinstance(dom, HTMLElement):
        element_stack = dom.childs if dom.isTag() else [dom]
    elif isinstance(dom, string_type):
        element_stack = parseString(dom).childs
    else:
        element_stack = dom

    # remove all tags
    output = ""
    while element_stack:
        el = element_stack.pop(0)

        if not (el.isTag() or el.isComment() or not el.getTagName()):
            output += el.__str__()

        if el.childs:
            element_stack = el.childs + element_stack

    return output