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

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

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

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

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

class F:
    def __init__(self, txt: str):
        self.u: C = None
        self.t: D = None
        self.v: D = None
        self.s: A = None
        self.w: C = None
        self.txt = txt

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

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

class I:
    def __init__(self, txt: str):
        self.p: C = None
        self.u: A = None
        self.s: G = None
        self.t: G = None
        self.q: C = None
        self.txt = txt

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

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

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

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

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

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

class F:
    def __init__(self, txt: str):
        self.u: C = None
        self.t: D = None
        self.v: D = None
        self.s: A = None
        self.w: C = None
        self.txt = txt

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

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

class I:
    def __init__(self, txt: str):
        self.p: C = None
        self.u: A = None
        self.s: G = None
        self.t: G = None
        self.q: C = None
        self.txt = txt

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

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