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

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

class C:
    def __init__(self, txt: str):
        self.q: E = None
        self.t: G = None
        self.z: F = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.u: H = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.t: B = None
        self.txt = txt

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

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

class H:
    def __init__(self, txt: str):
        self.w: C = None
        self.x: A = None
        self.y: F = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.u: G = None
        self.v: B = None
        self.z: G = None
        self.p: C = None
        self.w: H = None
        self.txt = txt

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

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

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

class C:
    def __init__(self, txt: str):
        self.q: E = None
        self.t: G = None
        self.z: F = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.u: H = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.t: B = None
        self.txt = txt

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

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

class H:
    def __init__(self, txt: str):
        self.w: C = None
        self.x: A = None
        self.y: F = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.u: G = None
        self.v: B = None
        self.z: G = None
        self.p: C = None
        self.w: H = None
        self.txt = txt

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

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