def add_arguments(parser):
    """ Adds batcher arguments to the parser									 

    This function gets the parser containing user inputs
    It adds arguments and returns a parser
    The parsing of args is performed in the main script 
    """
    parser.add_argument('--batch-size', dest='batch_size', action='store',
        default=1000, type=int, help='Number of elements in each batch')
    parser.add_argument('--batch-start', dest='batch_start', action='store',
        default=0, type=int, help='starts importing batches from a given batch'
        )
    parser.add_argument('--max-batches', dest='max_batches', action='store',
        default=None, type=int, help='Maximum amount of batches imported')
    parser.add_argument('--percentage', dest='percentage', action='store',
        default=None, type=int, help=
        'Percentage of elements to be randomly sampled (0-100%%)')
    parser.add_argument('--seed', dest='seed', action='store', default=None,
        type=int, help='Seed to reproduce last imported batch')
