class A:
    def __init__(self, txt: str):
        self.s: J = None
        self.t: I = None
        self.q: G = None
        self.v: E = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.p: J = None
        self.w: I = None
        self.z: D = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.w: I = None
        self.q: E = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.u: G = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.w: B = None
        self.z: D = None
        self.txt = txt

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

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

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

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

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

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

class B:
    def __init__(self, txt: str):
        self.p: J = None
        self.w: I = None
        self.z: D = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.w: I = None
        self.q: E = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.u: G = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.w: B = None
        self.z: D = None
        self.txt = txt

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

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

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

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

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

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