def get_signature_algorithm(alg_type, alg_hash):
    """
        Returns signature algorithm for ACM PCA 

        Args:
            isEC: true if Elliptic Curve certificate
            alg_type: Hash Algorithm from cryptography package to find

        Raises:
            ValueError: Algorithm type not supported
    """

    signing_algorithms = {
        "RSA": {
            "sha256": "SHA256WITHRSA",
            "sha384": "SHA384WITHRSA",
            "sha512": "SHA512WITHRSA"  
        },
        "ECDSA": {
            "sha256": "SHA256WITHECDSA",
            "sha384": "SHA384WITHECDSA",
            "sha512": "SHA512WITHECDSA" 
        }
    }
    if alg_hash not in ['sha256', 'sha384', 'sha512']:
        return ValueError('Signing Algorithm not supported')

    return signing_algorithms[alg_type][alg_hash]