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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_bytes(str_or_bytes, encoding='utf-8', errors='strict'):
 """Ensures an input is bytes, encoding if it is a string. """

    if isinstance(str_or_bytes, six.text_type):
        return str_or_bytes.encode(encoding, errors)
    return str_or_bytes