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

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

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

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

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

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

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

class H:
    def __init__(self, txt: str):
        self.o: B = None
        self.v: A = None
        self.q: B = None
        self.t: I = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.r: H = None
        self.p: F = None
        self.txt = txt

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

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

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

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

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

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

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

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

class H:
    def __init__(self, txt: str):
        self.o: B = None
        self.v: A = None
        self.q: B = None
        self.t: I = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.r: H = None
        self.p: F = None
        self.txt = txt

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

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