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

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

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

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

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

class F:
    def __init__(self, txt: str):
        self.s: C = None
        self.q: C = None
        self.r: B = None
        self.u: B = None
        self.t: I = None
        self.w: I = None
        self.v: B = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.o: A = None
        self.r: E = None
        self.q: D = None
        self.txt = txt

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

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

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

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

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

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

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

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

class F:
    def __init__(self, txt: str):
        self.s: C = None
        self.q: C = None
        self.r: B = None
        self.u: B = None
        self.t: I = None
        self.w: I = None
        self.v: B = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.o: A = None
        self.r: E = None
        self.q: D = None
        self.txt = txt

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

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

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

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