class A:
    def __init__(self, txt: str):
        self.u: H = None
        self.s: H = None
        self.txt = txt

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

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

class D:
    def __init__(self, txt: str):
        self.q: C = None
        self.o: F = None
        self.r: C = None
        self.w: B = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.z: C = None
        self.o: D = None
        self.r: D = None
        self.s: D = None
        self.x: B = None
        self.u: D = None
        self.t: B = None
        self.y: B = None
        self.txt = txt

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

class G:
    def __init__(self, txt: str):
        self.t: A = None
        self.q: H = None
        self.s: C = None
        self.y: E = None
        self.z: D = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.y: B = None
        self.s: D = None
        self.t: C = None
        self.o: F = None
        self.txt = txt

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

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

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

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

class D:
    def __init__(self, txt: str):
        self.q: C = None
        self.o: F = None
        self.r: C = None
        self.w: B = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.z: C = None
        self.o: D = None
        self.r: D = None
        self.s: D = None
        self.x: B = None
        self.u: D = None
        self.t: B = None
        self.y: B = None
        self.txt = txt

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

class G:
    def __init__(self, txt: str):
        self.t: A = None
        self.q: H = None
        self.s: C = None
        self.y: E = None
        self.z: D = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.y: B = None
        self.s: D = None
        self.t: C = None
        self.o: F = None
        self.txt = txt

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

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