class A:
    def __init__(self, txt: str):
        self.p: D = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.s: E = None
        self.txt = txt

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

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

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

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

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

class H:
    def __init__(self, txt: str):
        self.y: I = None
        self.x: G = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.z: H = None
        self.v: E = None
        self.txt = txt

k = A("k")
h = B("h")
e = C("e")
b = D("b")
c = E("c")
n = F("n")
g = G("g")
i = H("i")
f = I("f")
l = D("l")

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

class B:
    def __init__(self, txt: str):
        self.s: E = None
        self.txt = txt

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

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

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

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

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

class H:
    def __init__(self, txt: str):
        self.y: I = None
        self.x: G = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.z: H = None
        self.v: E = None
        self.txt = txt

k = A("k")
h = B("h")
e = C("e")
b = D("b")
c = E("c")
n = F("n")
g = G("g")
i = H("i")
f = I("f")
l = D("l")

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