class A:
    def __init__(self, txt: str):
        self.t: C = None
        self.y: B = None
        self.txt = txt

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

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

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

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

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

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

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

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

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

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

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

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

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

m.t = i
m.y = k
n.v = g
n.q = c
n.w = c
n.r = j
n.o = j
n.t = k
i.y = n
i.q = c
i.r = k
i.p = h
i.s = h
i.t = j
h.y = i
h.p = c
c.y = h
c.z = l
c.u = l
c.s = n
c.w = i
l.z = h
l.r = d
k.v = g
k.q = c
k.w = c
k.r = l
k.o = l
k.t = n
g.t = i
g.y = k
j.z = h
j.r = h
d.y = i
d.p = c
assert n.v.t.s.y.p.p.w.q.txt == "c"