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

class B:
    def __init__(self, txt: str):
        self.v: I = None
        self.s: H = None
        self.t: D = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.z: I = None
        self.w: F = None
        self.p: F = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.w: C = None
        self.q: F = None
        self.s: B = None
        self.t: F = None
        self.o: G = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.t: G = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.y: E = None
        self.x: E = None
        self.o: H = None
        self.v: I = None
        self.q: C = None
        self.w: E = None
        self.t: I = None
        self.u: C = None
        self.txt = txt

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

class I:
    def __init__(self, txt: str):
        self.y: D = None
        self.t: H = None
        self.p: E = None
        self.o: F = None
        self.u: B = None
        self.z: F = None
        self.v: B = None
        self.txt = txt

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

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

class B:
    def __init__(self, txt: str):
        self.v: I = None
        self.s: H = None
        self.t: D = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.z: I = None
        self.w: F = None
        self.p: F = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.w: C = None
        self.q: F = None
        self.s: B = None
        self.t: F = None
        self.o: G = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.t: G = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.y: E = None
        self.x: E = None
        self.o: H = None
        self.v: I = None
        self.q: C = None
        self.w: E = None
        self.t: I = None
        self.u: C = None
        self.txt = txt

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

class I:
    def __init__(self, txt: str):
        self.y: D = None
        self.t: H = None
        self.p: E = None
        self.o: F = None
        self.u: B = None
        self.z: F = None
        self.v: B = None
        self.txt = txt

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

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