class A:
    def __init__(self, txt: str):
        self.o: F = None
        self.y: F = None
        self.u: I = None
        self.r: F = None
        self.txt = txt

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

class C:
    def __init__(self, txt: str):
        self.r: H = None
        self.v: D = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.y: C = None
        self.r: G = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.w: G = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.p: B = None
        self.y: B = None
        self.u: A = None
        self.v: B = None
        self.txt = txt

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

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

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

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

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

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

class C:
    def __init__(self, txt: str):
        self.r: H = None
        self.v: D = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.y: C = None
        self.r: G = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.w: G = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.p: B = None
        self.y: B = None
        self.u: A = None
        self.v: B = None
        self.txt = txt

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

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

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

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

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