class A:
    def __init__(self, txt: str):
        self.z: F = None
        self.u: D = None
        self.r: B = None
        self.o: G = None
        self.s: C = None
        self.t: C = None
        self.p: G = None
        self.txt = txt

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

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

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

class E:
    def __init__(self, txt: str):
        self.z: B = None
        self.v: C = None
        self.y: E = None
        self.txt = txt

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

class G:
    def __init__(self, txt: str):
        self.y: F = None
        self.q: D = None
        self.txt = txt

g = A("g")
b = B("b")
h = C("h")
c = D("c")
a = E("a")
k = F("k")
l = G("l")
d = E("d")
f = B("f")
i = F("i")

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

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

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

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

class E:
    def __init__(self, txt: str):
        self.z: B = None
        self.v: C = None
        self.y: E = None
        self.txt = txt

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

class G:
    def __init__(self, txt: str):
        self.y: F = None
        self.q: D = None
        self.txt = txt

g = A("g")
b = B("b")
h = C("h")
c = D("c")
a = E("a")
k = F("k")
l = G("l")
d = E("d")
f = B("f")
i = F("i")

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