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

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

class C:
    def __init__(self, txt: str):
        self.z: G = None
        self.p: I = None
        self.w: G = None
        self.s: H = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.t: A = None
        self.z: J = None
        self.y: G = None
        self.p: I = None
        self.v: B = None
        self.q: D = None
        self.txt = txt

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

class G:
    def __init__(self, txt: str):
        self.z: E = None
        self.p: J = None
        self.x: H = None
        self.v: B = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.w: I = None
        self.txt = txt

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

class J:
    def __init__(self, txt: str):
        self.w: G = None
        self.o: B = None
        self.x: B = None
        self.txt = txt

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

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

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

class C:
    def __init__(self, txt: str):
        self.z: G = None
        self.p: I = None
        self.w: G = None
        self.s: H = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.t: A = None
        self.z: J = None
        self.y: G = None
        self.p: I = None
        self.v: B = None
        self.q: D = None
        self.txt = txt

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

class G:
    def __init__(self, txt: str):
        self.z: E = None
        self.p: J = None
        self.x: H = None
        self.v: B = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.w: I = None
        self.txt = txt

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

class J:
    def __init__(self, txt: str):
        self.w: G = None
        self.o: B = None
        self.x: B = None
        self.txt = txt

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

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