def get_authorization_token(registryIds=None):
    """
    Retrieves a token that is valid for a specified registry for 12 hours. This command allows you to use the docker CLI to push and pull images with Amazon ECR. If you do not specify a registry, the default registry is assumed.
    The authorizationToken returned for each registry specified is a base64 encoded string that can be decoded and used in a docker login command to authenticate to a registry. The AWS CLI offers an aws ecr get-login command that simplifies the login process.
    See also: AWS API Documentation
    
    Examples
    This example gets an authorization token for your default registry.
    Expected Output:
    
    :example: response = client.get_authorization_token(
        registryIds=[
            'string',
        ]
    )
    
    
    :type registryIds: list
    :param registryIds: A list of AWS account IDs that are associated with the registries for which to get authorization tokens. If you do not specify a registry, the default registry is assumed.
            (string) --
            

    :rtype: dict
    :return: {
        'authorizationData': [
            {
                'authorizationToken': 'string',
                'expiresAt': datetime(2015, 1, 1),
                'proxyEndpoint': 'string'
            },
        ]
    }
    
    
    """
    pass
