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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 ensure_index(index_like, copy=False):
 """ Ensure that we have an index from some index-like object. Parameters index : sequence An Index or other sequence copy : bool Returns ------- index : Index or MultiIndex Examples -------- Index(['a', 'b'], dtype='object') Index([('a', 'a'), ('b', 'c')], dtype='object') MultiIndex(levels=[['a'], ['b', 'c']], codes=[[0, 0], [0, 1]]) See Also -------- ensure_index_from_sequences """

    if isinstance(index_like, Index):
        if copy:
            index_like = index_like.copy()
        return index_like
    if hasattr(index_like, 'name'):
        return Index(index_like, name=index_like.name, copy=copy)

    if is_iterator(index_like):
        index_like = list(index_like)

    # must check for exactly list here because of strict type
    # check in clean_index_list
    if isinstance(index_like, list):
        if type(index_like) != list:
            index_like = list(index_like)

        converted, all_arrays = lib.clean_index_list(index_like)

        if len(converted) > 0 and all_arrays:
            from .multi import MultiIndex
            return MultiIndex.from_arrays(converted)
        else:
            index_like = converted
    else:
        # clean_index_list does the equivalent of copying
        # so only need to do this if not list instance
        if copy:
            from copy import copy
            index_like = copy(index_like)

    return Index(index_like)