class A:
    def __init__(self, txt: str):
        self.y: D = None
        self.o: E = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.v: C = None
        self.w: G = None
        self.p: G = None
        self.y: H = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.w: C = None
        self.y: A = None
        self.s: A = None
        self.t: C = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.w: D = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.o: H = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.q: G = None
        self.x: B = None
        self.w: A = None
        self.v: A = None
        self.y: A = None
        self.u: G = None
        self.p: D = None
        self.r: F = None
        self.txt = txt

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

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

class B:
    def __init__(self, txt: str):
        self.v: C = None
        self.w: G = None
        self.p: G = None
        self.y: H = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.w: C = None
        self.y: A = None
        self.s: A = None
        self.t: C = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.w: D = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.o: H = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.q: G = None
        self.x: B = None
        self.w: A = None
        self.v: A = None
        self.y: A = None
        self.u: G = None
        self.p: D = None
        self.r: F = None
        self.txt = txt

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

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