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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 _remove_unicode_keys(dictobj):
 """Convert keys from 'unicode' to 'str' type. workaround for <http://bugs.python.org/issue2646> """

    if sys.version_info[:2] >= (3, 0): return dictobj

    assert isinstance(dictobj, dict)

    newdict = {}
    for key, value in dictobj.items():
        if type(key) is unicode:
            key = key.encode('utf-8')
        newdict[key] = value
    return newdict