class A:
    def __init__(self, txt: str):
        self.t: I = None
        self.v: C = None
        self.y: J = None
        self.u: B = None
        self.w: E = None
        self.o: F = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.q: G = None
        self.w: A = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.s: J = None
        self.v: B = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.q: I = None
        self.y: B = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.u: H = None
        self.y: J = None
        self.w: H = None
        self.p: C = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.z: J = None
        self.r: J = None
        self.p: B = None
        self.q: I = None
        self.y: J = None
        self.x: I = None
        self.t: I = None
        self.w: C = None
        self.s: A = None
        self.u: C = None
        self.txt = txt

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

class J:
    def __init__(self, txt: str):
        self.x: F = None
        self.p: E = None
        self.z: E = None
        self.v: A = None
        self.u: I = None
        self.t: D = None
        self.w: I = None
        self.txt = txt

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

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

class B:
    def __init__(self, txt: str):
        self.q: G = None
        self.w: A = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.s: J = None
        self.v: B = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.q: I = None
        self.y: B = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.u: H = None
        self.y: J = None
        self.w: H = None
        self.p: C = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.z: J = None
        self.r: J = None
        self.p: B = None
        self.q: I = None
        self.y: J = None
        self.x: I = None
        self.t: I = None
        self.w: C = None
        self.s: A = None
        self.u: C = None
        self.txt = txt

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

class J:
    def __init__(self, txt: str):
        self.x: F = None
        self.p: E = None
        self.z: E = None
        self.v: A = None
        self.u: I = None
        self.t: D = None
        self.w: I = None
        self.txt = txt

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

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