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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 purge_duplicates(list_in):
 """Remove duplicates from list while preserving order. Parameters list_in: Iterable Returns ------- list List of first occurences in order """

    _list = []
    for item in list_in:
        if item not in _list:
            _list.append(item)
    return _list