Renaming ternary columns doesn't work

[s-leroux]

This fails on the print statement:

from fin.seq.serie import Serie
from fin.seq import fc

ser = Serie.create(
        (fc.named("T"), fc.range(10)),
        (fc.named("X"), "T"),
        (fc.named("Y"), fc.all, "X"),
    )
print(ser)

But that works as expected:

from fin.seq.serie import Serie
from fin.seq import fc

ser = Serie.create(
        (fc.named("T"), fc.range(10)),
        (fc.named("X"), "T"),
        (fc.all, "X"),
    )
print(ser)