class A:
    def __init__(self, txt: str):
        self.z: D = None
        self.x: E = None
        self.s: D = None
        self.v: G = None
        self.u: F = None
        self.q: G = None
        self.t: G = None
        self.txt = txt

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

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

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

class E:
    def __init__(self, txt: str):
        self.t: A = None
        self.s: C = None
        self.v: A = None
        self.z: G = None
        self.y: H = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.v: H = None
        self.w: G = None
        self.p: C = None
        self.y: E = None
        self.x: C = None
        self.u: D = None
        self.txt = txt

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

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

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

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

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

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

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

class E:
    def __init__(self, txt: str):
        self.t: A = None
        self.s: C = None
        self.v: A = None
        self.z: G = None
        self.y: H = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.v: H = None
        self.w: G = None
        self.p: C = None
        self.y: E = None
        self.x: C = None
        self.u: D = None
        self.txt = txt

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

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

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

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