import vcsn
c = vcsn.context('expressionset<lal, q>, q')
c
Beware that the following polynomial (admittedly badly displayed) is $\langle 2 \rangle \odot (a+b)$, not $\langle 2 \rangle \odot a \oplus b$: it contains a single expression, $a+b$.
p1 = c.polynomial('<2>a+b')
p1
p1.split()
p2 = c.polynomial('a+b(c+d)')
p2
p2.split()
p1 + p2
(p1 + p2).split()