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

class B:
    def __init__(self, txt: str):
        self.x: A = None
        self.p: G = None
        self.w: G = None
        self.s: A = None
        self.t: E = None
        self.z: I = None
        self.r: E = None
        self.o: G = None
        self.q: A = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.o: D = None
        self.w: E = None
        self.v: B = None
        self.p: B = None
        self.s: I = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.y: I = None
        self.o: G = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.w: H = None
        self.y: I = None
        self.t: I = None
        self.v: G = None
        self.s: H = None
        self.o: G = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.r: I = None
        self.v: F = None
        self.z: I = None
        self.u: A = None
        self.y: B = None
        self.q: F = None
        self.txt = txt

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

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

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

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

class B:
    def __init__(self, txt: str):
        self.x: A = None
        self.p: G = None
        self.w: G = None
        self.s: A = None
        self.t: E = None
        self.z: I = None
        self.r: E = None
        self.o: G = None
        self.q: A = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.o: D = None
        self.w: E = None
        self.v: B = None
        self.p: B = None
        self.s: I = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.y: I = None
        self.o: G = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.w: H = None
        self.y: I = None
        self.t: I = None
        self.v: G = None
        self.s: H = None
        self.o: G = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.r: I = None
        self.v: F = None
        self.z: I = None
        self.u: A = None
        self.y: B = None
        self.q: F = None
        self.txt = txt

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

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

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

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