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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 encode_items(items):
 """Function that encode all elements in the list of items passed as a parameter :param items: A list of tuple :returns: A list of tuple with all items encoded in 'utf-8' """

    encoded = []
    for key, values in items:
        for value in values:
            encoded.append((key.encode('utf-8'), value.encode('utf-8')))
    return encoded