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

class B:
    def __init__(self, txt: str):
        self.v: A = None
        self.w: A = None
        self.r: A = None
        self.s: B = None
        self.q: H = None
        self.x: B = None
        self.z: D = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.y: E = None
        self.r: B = None
        self.txt = txt

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

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

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

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

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

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

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

class B:
    def __init__(self, txt: str):
        self.v: A = None
        self.w: A = None
        self.r: A = None
        self.s: B = None
        self.q: H = None
        self.x: B = None
        self.z: D = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.y: E = None
        self.r: B = None
        self.txt = txt

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

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

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

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

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

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

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