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

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

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

class D:
    def __init__(self, txt: str):
        self.y: A = None
        self.s: C = None
        self.r: B = None
        self.o: B = None
        self.q: A = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.q: D = None
        self.p: D = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.y: E = None
        self.x: E = None
        self.v: C = None
        self.txt = txt

e = A("e")
j = B("j")
c = C("c")
k = D("k")
f = E("f")
n = F("n")
b = D("b")
l = B("l")

e.p = j
e.v = b
e.z = n
e.w = f
e.t = f
e.o = l
j.t = n
j.s = f
j.p = c
j.v = l
c.q = n
c.z = n
c.r = n
c.p = e
c.o = e
c.t = k
k.y = e
k.q = e
k.s = c
k.r = l
k.o = j
f.q = k
f.p = b
n.y = f
n.x = f
n.v = c
b.y = e
b.q = e
b.s = c
b.r = l
b.o = l
l.t = n
l.s = f
l.p = c
l.v = j
assert f.q.o.v.s.q.o.t.txt == "
class A:
    def __init__(self, txt: str):
        self.p: B = None
        self.v: D = None
        self.z: F = None
        self.w: E = None
        self.o: B = None
        self.t: E = None
        self.txt = txt

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

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

class D:
    def __init__(self, txt: str):
        self.y: A = None
        self.s: C = None
        self.r: B = None
        self.o: B = None
        self.q: A = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.q: D = None
        self.p: D = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.y: E = None
        self.x: E = None
        self.v: C = None
        self.txt = txt

e = A("e")
j = B("j")
c = C("c")
k = D("k")
f = E("f")
n = F("n")
b = D("b")
l = B("l")

e.p = j
e.v = b
e.z = n
e.w = f
e.t = f
e.o = l
j.t = n
j.s = f
j.p = c
j.v = l
c.q = n
c.z = n
c.r = n
c.p = e
c.o = e
c.t = k
k.y = e
k.q = e
k.s = c
k.r = l
k.o = j
f.q = k
f.p = b
n.y = f
n.x = f
n.v = c
b.y = e
b.q = e
b.s = c
b.r = l
b.o = l
l.t = n
l.s = f
l.p = c
l.v = j
assert f.q.o.v.s.q.o.t.txt == "n"