class A:
    def __init__(self, txt: str):
        self.t: D = None
        self.z: B = None
        self.w: E = None
        self.y: D = None
        self.x: G = None
        self.v: D = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.x: C = None
        self.o: F = None
        self.q: G = None
        self.r: E = None
        self.y: C = None
        self.z: A = None
        self.t: D = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.v: H = None
        self.s: F = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.p: F = None
        self.x: C = None
        self.v: C = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.o: C = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.s: F = None
        self.u: G = None
        self.v: G = None
        self.y: A = None
        self.z: G = None
        self.o: E = None
        self.txt = txt

g = A("g")
i = B("i")
c = C("c")
j = D("j")
a = E("a")
l = F("l")
f = G("f")
b = H("b")

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

class B:
    def __init__(self, txt: str):
        self.x: C = None
        self.o: F = None
        self.q: G = None
        self.r: E = None
        self.y: C = None
        self.z: A = None
        self.t: D = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.v: H = None
        self.s: F = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.p: F = None
        self.x: C = None
        self.v: C = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.o: C = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.s: F = None
        self.u: G = None
        self.v: G = None
        self.y: A = None
        self.z: G = None
        self.o: E = None
        self.txt = txt

g = A("g")
i = B("i")
c = C("c")
j = D("j")
a = E("a")
l = F("l")
f = G("f")
b = H("b")

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