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

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

class C:
    def __init__(self, txt: str):
        self.x: B = None
        self.p: I = None
        self.o: I = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.p: C = None
        self.s: B = None
        self.z: I = None
        self.y: C = None
        self.r: B = None
        self.u: G = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.t: B = None
        self.z: I = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.o: A = None
        self.t: E = None
        self.y: E = None
        self.r: I = None
        self.v: H = None
        self.z: H = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.y: A = None
        self.o: D = None
        self.z: I = None
        self.t: I = None
        self.v: I = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.o: C = None
        self.w: D = None
        self.txt = txt

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

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

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

class C:
    def __init__(self, txt: str):
        self.x: B = None
        self.p: I = None
        self.o: I = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.p: C = None
        self.s: B = None
        self.z: I = None
        self.y: C = None
        self.r: B = None
        self.u: G = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.t: B = None
        self.z: I = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.o: A = None
        self.t: E = None
        self.y: E = None
        self.r: I = None
        self.v: H = None
        self.z: H = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.y: A = None
        self.o: D = None
        self.z: I = None
        self.t: I = None
        self.v: I = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.o: C = None
        self.w: D = None
        self.txt = txt

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

g.s = i
g.w = k
g.v = e
g.u = f
i.r = d
d.x = i
d.p = f
d.o = f
k.p = d
k.y = d
k.s = i
k.r = i
k.z = f
k.u = c
l.w = i
l.p = j
l.r = d
l.q = e
l.z = f
j.t = i
j.z = f
c.o = g
c.t = l
c.y = l
c.r = f
c.v = e
c.z = e
e.y = g
e.o = k
e.z = f
e.t = f
e.v = f
f.o = d
f.w = k
assert g.w.u.y.p.t.r.p.w.y.txt == "d"