class A:
    def __init__(self, txt: str):
        self.s: H = None
        self.x: E = None
        self.txt = txt

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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