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

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

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

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

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

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

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

g.q = j
n.y = k
n.r = i
n.v = j
n.p = m
h.s = j
i.z = h
i.y = g
i.u = f
i.t = a
m.y = i
m.z = i
m.q = i
m.x = n
m.p = a
j.p = a
j.v = f
j.u = i
j.t = i
k.y = i
k.z = i
k.q = i
k.x = a
k.p = a
l.p = a
l.v = g
l.u = i
l.t = i
f.q = j
a.y = k
a.p = k
a.r = i
a.v = j
assert m.y.z.s.t.t.v.v.q.p.y.txt == "
class A:
    def __init__(self, txt: str):
        self.q: F = None
        self.txt = txt

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

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

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

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

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

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

g.q = j
n.y = k
n.r = i
n.v = j
n.p = m
h.s = j
i.z = h
i.y = g
i.u = f
i.t = a
m.y = i
m.z = i
m.q = i
m.x = n
m.p = a
j.p = a
j.v = f
j.u = i
j.t = i
k.y = i
k.z = i
k.q = i
k.x = a
k.p = a
l.p = a
l.v = g
l.u = i
l.t = i
f.q = j
a.y = k
a.p = k
a.r = i
a.v = j
assert m.y.z.s.t.t.v.v.q.p.y.txt == "k"