class A:
    def __init__(self, txt: str):
        self.y: B = None
        self.q: B = None
        self.r: I = None
        self.u: D = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.u: E = None
        self.x: D = None
        self.v: F = None
        self.s: H = None
        self.w: F = None
        self.txt = txt

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

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

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

class F:
    def __init__(self, txt: str):
        self.q: C = None
        self.y: G = None
        self.t: G = None
        self.r: B = None
        self.x: H = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.q: D = None
        self.t: B = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.v: F = None
        self.o: H = None
        self.x: G = None
        self.z: F = None
        self.txt = txt

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

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

class B:
    def __init__(self, txt: str):
        self.u: E = None
        self.x: D = None
        self.v: F = None
        self.s: H = None
        self.w: F = None
        self.txt = txt

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

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

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

class F:
    def __init__(self, txt: str):
        self.q: C = None
        self.y: G = None
        self.t: G = None
        self.r: B = None
        self.x: H = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.q: D = None
        self.t: B = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.v: F = None
        self.o: H = None
        self.x: G = None
        self.z: F = None
        self.txt = txt

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

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