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

class B:
    def __init__(self, txt: str):
        self.t: H = None
        self.p: E = None
        self.v: E = None
        self.x: D = None
        self.u: D = None
        self.o: E = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.r: B = None
        self.w: H = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.r: E = None
        self.t: B = None
        self.w: A = None
        self.u: H = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.q: B = None
        self.v: F = None
        self.r: I = None
        self.w: H = None
        self.z: G = None
        self.p: G = None
        self.o: B = None
        self.txt = txt

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

class G:
    def __init__(self, txt: str):
        self.y: B = None
        self.o: H = None
        self.u: B = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.u: D = None
        self.r: B = None
        self.v: G = None
        self.t: I = None
        self.txt = txt

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

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

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

class B:
    def __init__(self, txt: str):
        self.t: H = None
        self.p: E = None
        self.v: E = None
        self.x: D = None
        self.u: D = None
        self.o: E = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.r: B = None
        self.w: H = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.r: E = None
        self.t: B = None
        self.w: A = None
        self.u: H = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.q: B = None
        self.v: F = None
        self.r: I = None
        self.w: H = None
        self.z: G = None
        self.p: G = None
        self.o: B = None
        self.txt = txt

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

class G:
    def __init__(self, txt: str):
        self.y: B = None
        self.o: H = None
        self.u: B = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.u: D = None
        self.r: B = None
        self.v: G = None
        self.t: I = None
        self.txt = txt

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

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

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