def describe_luna_client(ClientArn=None, CertificateFingerprint=None):
    """
    Retrieves information about an HSM client.
    See also: AWS API Documentation
    
    
    :example: response = client.describe_luna_client(
        ClientArn='string',
        CertificateFingerprint='string'
    )
    
    
    :type ClientArn: string
    :param ClientArn: The ARN of the client.

    :type CertificateFingerprint: string
    :param CertificateFingerprint: The certificate fingerprint.

    :rtype: dict
    :return: {
        'ClientArn': 'string',
        'Certificate': 'string',
        'CertificateFingerprint': 'string',
        'LastModifiedTimestamp': 'string',
        'Label': 'string'
    }
    
    
    """
    pass
