class A:
    def __init__(self, txt: str):
        self.y: I = None
        self.r: I = None
        self.o: C = None
        self.p: H = None
        self.u: I = None
        self.s: J = None
        self.x: E = None
        self.z: J = None
        self.v: I = None
        self.txt = txt

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

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

class D:
    def __init__(self, txt: str):
        self.q: A = None
        self.u: H = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.v: J = None
        self.o: A = None
        self.r: I = None
        self.u: C = None
        self.s: F = None
        self.x: D = None
        self.txt = txt

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

class G:
    def __init__(self, txt: str):
        self.s: A = None
        self.y: D = None
        self.u: B = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.z: A = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.w: A = None
        self.o: H = None
        self.s: H = None
        self.r: D = None
        self.v: C = None
        self.z: D = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.t: G = None
        self.u: I = None
        self.w: I = None
        self.txt = txt

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

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

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

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

class D:
    def __init__(self, txt: str):
        self.q: A = None
        self.u: H = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.v: J = None
        self.o: A = None
        self.r: I = None
        self.u: C = None
        self.s: F = None
        self.x: D = None
        self.txt = txt

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

class G:
    def __init__(self, txt: str):
        self.s: A = None
        self.y: D = None
        self.u: B = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.z: A = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.w: A = None
        self.o: H = None
        self.s: H = None
        self.r: D = None
        self.v: C = None
        self.z: D = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.t: G = None
        self.u: I = None
        self.w: I = None
        self.txt = txt

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

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