class A:
    def __init__(self, txt: str):
        self.y: D = None
        self.o: D = None
        self.x: G = None
        self.s: F = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.x: H = None
        self.u: C = None
        self.w: G = None
        self.r: D = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.x: A = None
        self.q: D = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.x: A = None
        self.o: A = None
        self.s: C = None
        self.u: D = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.s: H = None
        self.q: F = None
        self.x: C = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.p: C = None
        self.q: A = None
        self.u: G = None
        self.s: D = None
        self.o: C = None
        self.t: E = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.x: H = None
        self.o: B = None
        self.u: D = None
        self.z: B = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.p: A = None
        self.w: D = None
        self.r: E = None
        self.t: D = None
        self.v: A = None
        self.o: F = None
        self.txt = txt

i = A("i")
n = B("n")
b = C("b")
f = D("f")
g = E("g")
e = F("e")
d = G("d")
j = H("j")
c = D("c")
m = E("m")

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

class B:
    def __init__(self, txt: str):
        self.x: H = None
        self.u: C = None
        self.w: G = None
        self.r: D = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.x: A = None
        self.q: D = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.x: A = None
        self.o: A = None
        self.s: C = None
        self.u: D = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.s: H = None
        self.q: F = None
        self.x: C = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.p: C = None
        self.q: A = None
        self.u: G = None
        self.s: D = None
        self.o: C = None
        self.t: E = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.x: H = None
        self.o: B = None
        self.u: D = None
        self.z: B = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.p: A = None
        self.w: D = None
        self.r: E = None
        self.t: D = None
        self.v: A = None
        self.o: F = None
        self.txt = txt

i = A("i")
n = B("n")
b = C("b")
f = D("f")
g = E("g")
e = F("e")
d = G("d")
j = H("j")
c = D("c")
m = E("m")

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