class A:
    def __init__(self, txt: str):
        self.v: E = None
        self.txt = txt

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

class C:
    def __init__(self, txt: str):
        self.o: E = None
        self.z: F = None
        self.s: F = None
        self.x: B = None
        self.txt = txt

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

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

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

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

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

class I:
    def __init__(self, txt: str):
        self.u: F = None
        self.s: H = None
        self.q: A = None
        self.t: C = None
        self.z: H = None
        self.txt = txt

i = A("i")
b = B("b")
j = C("j")
h = D("h")
a = E("a")
f = F("f")
n = G("n")
e = H("e")
l = I("l")

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

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

class C:
    def __init__(self, txt: str):
        self.o: E = None
        self.z: F = None
        self.s: F = None
        self.x: B = None
        self.txt = txt

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

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

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

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

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

class I:
    def __init__(self, txt: str):
        self.u: F = None
        self.s: H = None
        self.q: A = None
        self.t: C = None
        self.z: H = None
        self.txt = txt

i = A("i")
b = B("b")
j = C("j")
h = D("h")
a = E("a")
f = F("f")
n = G("n")
e = H("e")
l = I("l")

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