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

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

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

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

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

class F:
    def __init__(self, txt: str):
        self.v: E = None
        self.w: E = None
        self.y: D = None
        self.p: B = None
        self.txt = txt

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

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

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

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

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

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

class F:
    def __init__(self, txt: str):
        self.v: E = None
        self.w: E = None
        self.y: D = None
        self.p: B = None
        self.txt = txt

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

j.v = m
j.z = h
j.u = h
j.y = h
h.v = m
h.z = a
h.o = k
a.s = l
b.u = a
b.s = a
b.v = k
b.q = h
m.r = j
m.x = b
m.o = a
l.v = m
l.w = m
l.y = k
l.p = h
i.v = m
i.z = h
i.u = h
i.y = h
k.u = a
k.s = a
k.v = b
k.q = h
c.v = m
c.z = h
c.u = h
c.y = h
n.v = m
n.w = m
n.y = b
n.p = h
assert j.z.o.v.q.z.s.y.txt == "k"