removed unused argument
diff --git a/scripts/training/run_thrax.py b/scripts/training/run_thrax.py
index 11eaa5f..810844a 100755
--- a/scripts/training/run_thrax.py
+++ b/scripts/training/run_thrax.py
@@ -51,7 +51,6 @@
parser.add_argument('-v', dest='verbose', default=False, action='store_true', help='Be verbose')
parser.add_argument('-d', '--debug', dest='debug', default=False, action='store_true', help='Don\'t cleanup')
parser.add_argument('corpora', nargs='+', help='Either (a) the Thrax input file or (b) the source, target, and aligned corpus files')
-parser.add_argument('alignment_file', help='The alignment between them')
args = parser.parse_args()
HADOOP = os.environ['HADOOP']
