(key, date_stamp, region_name, service_name)
return k_signing
Calculates the signing key used to calculate the signature for
    AWS Signature Version 4 based on:
    https://docs.aws.amazon.com/general/latest/gr/sigv4-calculate-signature.html

    Args:
        key (str): The AWS secret access key.
        date_stamp (str): The '%Y%m%d' date format.
        region_name (str): The AWS region.
        service_name (str): The AWS service name, eg. sts.

    Returns:
        str: The signing key bytes.
Calculates the signing key used to calculate the signature for
    AWS Signature Version 4 based on:
    https://docs.aws.amazon.com/general/latest/gr/sigv4-calculate-signature.html
Calculates the signing key used to calculate the signature for AWS Signature Version 4 based on : https : // docs . aws . amazon . com / general / latest / gr / sigv4 - calculate - signature . html
def _get_signing_key(key, date_stamp, region_name, service_name):
    """Calculates the signing key used to calculate the signature for
    AWS Signature Version 4 based on:
    https://docs.aws.amazon.com/general/latest/gr/sigv4-calculate-signature.html

    Args:
        key (str): The AWS secret access key.
        date_stamp (str): The '%Y%m%d' date format.
        region_name (str): The AWS region.
        service_name (str): The AWS service name, eg. sts.

    Returns:
        str: The signing key bytes.
    """
    k_date = _sign(("AWS4" + key).encode("utf-8"), date_stamp)
    k_region = _sign(k_date, region_name)
    k_service = _sign(k_region, service_name)
    k_signing = _sign(k_service, "aws4_request")
    return k_signing
def _get_signing_key ( key , date_stamp , region_name , service_name ) : k_date = _sign ( ( "AWS4" + key ) . encode ( "utf-8" ) , date_stamp ) k_region = _sign ( k_date , region_name ) k_service = _sign ( k_region , service_name ) k_signing = _sign ( k_service , "aws4_request" ) return k_signing