class A:
    def __init__(self, txt: str):
        self.o: F = None
        self.w: H = None
        self.x: G = None
        self.v: I = None
        self.r: F = None
        self.y: I = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.u: E = None
        self.v: A = None
        self.w: E = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.z: A = None
        self.s: G = None
        self.o: F = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.p: G = None
        self.w: H = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.z: A = None
        self.y: C = None
        self.p: H = None
        self.w: H = None
        self.q: B = None
        self.o: F = None
        self.r: F = None
        self.u: C = None
        self.s: G = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.o: G = None
        self.u: E = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.p: H = None
        self.o: B = None
        self.y: F = None
        self.r: I = None
        self.q: B = None
        self.t: C = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.u: E = None
        self.w: B = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.u: B = None
        self.z: G = None
        self.r: E = None
        self.txt = txt

j = A("j")
k = B("k")
n = C("n")
f = D("f")
g = E("g")
l = F("l")
c = G("c")
b = H("b")
a = I("a")
i = H("i")

j.o = l
j.r = l
j.w = i
j.x = c
j.v = a
j.y = a
k.u = g
k.w = g
k.v = j
n.z = j
n.s = c
n.o = l
f.p = c
f.w = b
g.z = j
g.y = n
g.u = n
g.p = b
g.w = b
g.q = k
g.o = l
g.r = l
g.s = c
l.o = c
l.u = g
c.p = b
c.o = k
c.q = k
c.y = l
c.r = a
c.t = n
b.u = g
b.w = k
a.u = k
a.z = c
a.r = g
i.u = g
i.w = k
assert b.w.u.w.w.v.x.y.txt == "
class A:
    def __init__(self, txt: str):
        self.o: F = None
        self.w: H = None
        self.x: G = None
        self.v: I = None
        self.r: F = None
        self.y: I = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.u: E = None
        self.v: A = None
        self.w: E = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.z: A = None
        self.s: G = None
        self.o: F = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.p: G = None
        self.w: H = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.z: A = None
        self.y: C = None
        self.p: H = None
        self.w: H = None
        self.q: B = None
        self.o: F = None
        self.r: F = None
        self.u: C = None
        self.s: G = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.o: G = None
        self.u: E = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.p: H = None
        self.o: B = None
        self.y: F = None
        self.r: I = None
        self.q: B = None
        self.t: C = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.u: E = None
        self.w: B = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.u: B = None
        self.z: G = None
        self.r: E = None
        self.txt = txt

j = A("j")
k = B("k")
n = C("n")
f = D("f")
g = E("g")
l = F("l")
c = G("c")
b = H("b")
a = I("a")
i = H("i")

j.o = l
j.r = l
j.w = i
j.x = c
j.v = a
j.y = a
k.u = g
k.w = g
k.v = j
n.z = j
n.s = c
n.o = l
f.p = c
f.w = b
g.z = j
g.y = n
g.u = n
g.p = b
g.w = b
g.q = k
g.o = l
g.r = l
g.s = c
l.o = c
l.u = g
c.p = b
c.o = k
c.q = k
c.y = l
c.r = a
c.t = n
b.u = g
b.w = k
a.u = k
a.z = c
a.r = g
i.u = g
i.w = k
assert b.w.u.w.w.v.x.y.txt == "l"