class A:
    def __init__(self, txt: str):
        self.y: E = None
        self.t: G = None
        self.z: I = None
        self.p: H = None
        self.r: H = None
        self.w: G = None
        self.s: D = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.p: E = None
        self.s: I = None
        self.x: C = None
        self.w: D = None
        self.r: D = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.s: E = None
        self.t: H = None
        self.q: H = None
        self.r: A = None
        self.txt = txt

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

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

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

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

class I:
    def __init__(self, txt: str):
        self.u: D = None
        self.r: G = None
        self.y: F = None
        self.x: C = None
        self.o: B = None
        self.z: A = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.q: I = None
        self.y: I = None
        self.w: G = None
        self.txt = txt

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

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

class B:
    def __init__(self, txt: str):
        self.p: E = None
        self.s: I = None
        self.x: C = None
        self.w: D = None
        self.r: D = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.s: E = None
        self.t: H = None
        self.q: H = None
        self.r: A = None
        self.txt = txt

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

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

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

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

class I:
    def __init__(self, txt: str):
        self.u: D = None
        self.r: G = None
        self.y: F = None
        self.x: C = None
        self.o: B = None
        self.z: A = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.q: I = None
        self.y: I = None
        self.w: G = None
        self.txt = txt

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

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