class A:
    def __init__(self, txt: str):
        self.u: C = None
        self.p: D = None
        self.t: D = None
        self.o: E = None
        self.y: B = None
        self.txt = txt

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

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

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

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

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

g = A("g")
a = B("a")
l = C("l")
b = D("b")
m = E("m")
h = F("h")
i = E("i")
e = C("e")
j = A("j")

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

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

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

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

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

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

g = A("g")
a = B("a")
l = C("l")
b = D("b")
m = E("m")
h = F("h")
i = E("i")
e = C("e")
j = A("j")

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