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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 _sign_data(secret, data):
 """ Sign data. :param data: the string to sign :return: string base64 encoding of the HMAC-SHA1 hash of the data parameter using {@code secretKey} as cipher key. """

    sha1_hash = hmac.new(secret.encode(), data.encode(), sha1)
    return binascii.b2a_base64(sha1_hash.digest())[:-1].decode('utf8')