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

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

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

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

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

class F:
    def __init__(self, txt: str):
        self.r: E = None
        self.z: C = None
        self.w: B = None
        self.y: C = None
        self.q: C = None
        self.txt = txt

c = A("c")
a = B("a")
e = C("e")
n = D("n")
l = E("l")
j = F("j")
h = B("h")

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

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

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

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

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

class F:
    def __init__(self, txt: str):
        self.r: E = None
        self.z: C = None
        self.w: B = None
        self.y: C = None
        self.q: C = None
        self.txt = txt

c = A("c")
a = B("a")
e = C("e")
n = D("n")
l = E("l")
j = F("j")
h = B("h")

c.s = h
c.u = l
c.o = l
c.w = a
c.p = a
c.v = e
a.w = h
a.t = l
a.v = l
a.p = c
e.p = a
n.z = c
n.r = h
l.p = j
l.q = c
l.u = n
l.t = n
j.r = l
j.z = e
j.y = e
j.q = e
j.w = h
h.w = a
h.t = l
h.v = l
h.p = c
assert n.z.u.u.r.p.s.p.txt == "c"