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

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

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

class D:
    def __init__(self, txt: str):
        self.x: G = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.u: I = None
        self.t: D = None
        self.q: I = None
        self.x: B = None
        self.r: G = None
        self.w: D = None
        self.o: F = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.s: G = None
        self.x: E = None
        self.v: I = None
        self.txt = txt

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

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

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

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

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

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

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

class D:
    def __init__(self, txt: str):
        self.x: G = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.u: I = None
        self.t: D = None
        self.q: I = None
        self.x: B = None
        self.r: G = None
        self.w: D = None
        self.o: F = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.s: G = None
        self.x: E = None
        self.v: I = None
        self.txt = txt

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

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

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

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

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