Parser will not raise exceptions If you specify wrong year "201A".
Sample code:
from dateutil import parser
origin = "201A-01-01T23:58:39.239769+03:00"
parsed = parser.parse(origin)
print("origin={}".format(origin))
print("parsed={}".format(parsed.isoformat()))
Output:
origin=201A-01-01T23:58:39.239769+03:00
parsed=2017-03-22T23:58:39.239769+03:00
I use python3.5 on Mac.
dateutil version="2.6.0"