class A:
    def __init__(self, txt: str):
        self.t: D = None
        self.x: B = None
        self.u: F = None
        self.o: A = None
        self.y: F = None
        self.w: A = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.o: C = None
        self.w: E = None
        self.x: D = None
        self.q: A = None
        self.txt = txt

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

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

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

class F:
    def __init__(self, txt: str):
        self.u: E = None
        self.q: E = None
        self.s: C = None
        self.txt = txt

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

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

class B:
    def __init__(self, txt: str):
        self.o: C = None
        self.w: E = None
        self.x: D = None
        self.q: A = None
        self.txt = txt

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

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

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

class F:
    def __init__(self, txt: str):
        self.u: E = None
        self.q: E = None
        self.s: C = None
        self.txt = txt

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

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