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

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

class C:
    def __init__(self, txt: str):
        self.q: F = None
        self.t: I = None
        self.r: D = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.y: E = None
        self.p: I = None
        self.x: F = None
        self.q: H = None
        self.t: A = None
        self.txt = txt

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

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

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

class H:
    def __init__(self, txt: str):
        self.p: I = None
        self.t: C = None
        self.o: B = None
        self.s: F = None
        self.x: B = None
        self.txt = txt

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

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

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

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

class C:
    def __init__(self, txt: str):
        self.q: F = None
        self.t: I = None
        self.r: D = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.y: E = None
        self.p: I = None
        self.x: F = None
        self.q: H = None
        self.t: A = None
        self.txt = txt

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

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

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

class H:
    def __init__(self, txt: str):
        self.p: I = None
        self.t: C = None
        self.o: B = None
        self.s: F = None
        self.x: B = None
        self.txt = txt

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

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

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