def delete_faces(CollectionId=None, FaceIds=None):
    """
    Deletes faces from a collection. You specify a collection ID and an array of face IDs to remove from the collection.
    This operation requires permissions to perform the rekognition:DeleteFaces action.
    See also: AWS API Documentation
    
    Examples
    This operation deletes one or more faces from a Rekognition collection.
    Expected Output:
    
    :example: response = client.delete_faces(
        CollectionId='string',
        FaceIds=[
            'string',
        ]
    )
    
    
    :type CollectionId: string
    :param CollectionId: [REQUIRED]
            Collection from which to remove the specific faces.
            

    :type FaceIds: list
    :param FaceIds: [REQUIRED]
            An array of face IDs to delete.
            (string) --
            

    :rtype: dict
    :return: {
        'DeletedFaces': [
            'string',
        ]
    }
    
    
    :returns: 
    (string) --
    
    """
    pass
