class A:
    def __init__(self, txt: str):
        self.r: B = None
        self.u: F = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.v: C = None
        self.q: F = None
        self.s: F = None
        self.y: C = None
        self.z: E = None
        self.p: E = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.z: A = None
        self.r: E = None
        self.p: A = None
        self.y: F = None
        self.q: C = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.o: A = None
        self.w: C = None
        self.t: E = None
        self.txt = txt

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

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

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

class B:
    def __init__(self, txt: str):
        self.v: C = None
        self.q: F = None
        self.s: F = None
        self.y: C = None
        self.z: E = None
        self.p: E = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.z: A = None
        self.r: E = None
        self.p: A = None
        self.y: F = None
        self.q: C = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.o: A = None
        self.w: C = None
        self.t: E = None
        self.txt = txt

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

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

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