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

class B:
    def __init__(self, txt: str):
        self.v: C = None
        self.p: G = None
        self.t: C = None
        self.o: H = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.z: I = None
        self.v: H = None
        self.u: E = None
        self.x: H = None
        self.s: E = None
        self.o: I = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.v: A = None
        self.t: B = None
        self.w: C = None
        self.x: B = None
        self.z: G = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.s: G = None
        self.o: C = None
        self.t: H = None
        self.r: A = None
        self.w: I = None
        self.y: I = None
        self.p: C = None
        self.u: F = None
        self.v: I = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.v: A = None
        self.o: E = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.t: H = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.s: D = None
        self.r: I = None
        self.q: A = None
        self.w: I = None
        self.u: C = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.s: D = None
        self.o: H = None
        self.z: D = None
        self.u: I = None
        self.y: C = None
        self.p: D = None
        self.txt = txt

c = A("c")
a = B("a")
g = C("g")
i = D("i")
e = E("e")
b = F("b")
m = G("m")
h = H("h")
j = I("j")
l = I("l")

c.z = a
c.p = e
c.u = h
c.o = i
c.s = b
c.r = b
c.v = b
c.x = l
a.v = g
a.t = g
a.p = m
a.o = h
g.z = j
g.v = h
g.x = h
g.u = e
g.s = e
g.o = l
i.v = c
i.t = a
i.x = a
i.w = g
i.z = m
e.s = m
e.o = g
e.p = g
e.t = h
e.r = c
e.w = l
e.v = l
e.y = j
e.u = b
b.v = c
b.o = e
m.t = h
h.s = i
h.r = l
h.q = c
h.w = j
h.u = g
j.s = i
j.z = i
j.p = i
j.o = h
j.u = l
j.y = g
l.s = i
l.z = i
l.p = i
l.o = h
l.u = j
l.y = g
assert j.u.o.s.v.o.w.o.o.q.u.txt == "
class A:
    def __init__(self, txt: str):
        self.z: B = None
        self.p: E = None
        self.u: H = None
        self.o: D = None
        self.s: F = None
        self.r: F = None
        self.x: I = None
        self.v: F = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.v: C = None
        self.p: G = None
        self.t: C = None
        self.o: H = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.z: I = None
        self.v: H = None
        self.u: E = None
        self.x: H = None
        self.s: E = None
        self.o: I = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.v: A = None
        self.t: B = None
        self.w: C = None
        self.x: B = None
        self.z: G = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.s: G = None
        self.o: C = None
        self.t: H = None
        self.r: A = None
        self.w: I = None
        self.y: I = None
        self.p: C = None
        self.u: F = None
        self.v: I = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.v: A = None
        self.o: E = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.t: H = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.s: D = None
        self.r: I = None
        self.q: A = None
        self.w: I = None
        self.u: C = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.s: D = None
        self.o: H = None
        self.z: D = None
        self.u: I = None
        self.y: C = None
        self.p: D = None
        self.txt = txt

c = A("c")
a = B("a")
g = C("g")
i = D("i")
e = E("e")
b = F("b")
m = G("m")
h = H("h")
j = I("j")
l = I("l")

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