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

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

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

class D:
    def __init__(self, txt: str):
        self.t: B = None
        self.x: B = None
        self.txt = txt

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

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

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

a.t = c
a.s = c
a.p = k
a.z = l
a.u = e
e.w = a
e.p = n
l.o = m
l.x = m
l.p = a
l.s = b
l.q = k
b.t = e
b.x = n
c.v = a
k.p = c
k.q = c
m.t = n
m.x = n
n.w = a
n.p = e
assert m.x.w.p.p.v.u.txt == "
class A:
    def __init__(self, txt: str):
        self.t: E = None
        self.p: F = None
        self.s: E = None
        self.z: C = None
        self.u: B = None
        self.txt = txt

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

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

class D:
    def __init__(self, txt: str):
        self.t: B = None
        self.x: B = None
        self.txt = txt

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

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

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

a.t = c
a.s = c
a.p = k
a.z = l
a.u = e
e.w = a
e.p = n
l.o = m
l.x = m
l.p = a
l.s = b
l.q = k
b.t = e
b.x = n
c.v = a
k.p = c
k.q = c
m.t = n
m.x = n
n.w = a
n.p = e
assert m.x.w.p.p.v.u.txt == "e"