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

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

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

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

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

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

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

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

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

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

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

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

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

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

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