code: def colon_subscripts(u):
      
      if u.__class__ in (node.arrayref,node.cellarrayref):
          for w in u.args:
              if w.__class__ is node.expr and w.op == ":":
                  w._replace(op="::")
docs: Array colon subscripts foo(1:10) and colon expressions 1:10 look
      too similar to each other.  Now is the time to find out who is who.