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

class B:
    def __init__(self, txt: str):
        self.v: G = None
        self.s: E = None
        self.r: F = None
        self.txt = txt

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

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

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

class F:
    def __init__(self, txt: str):
        self.w: J = None
        self.v: A = None
        self.o: D = None
        self.t: B = None
        self.x: D = None
        self.q: A = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.o: J = None
        self.q: I = None
        self.z: D = None
        self.txt = txt

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

class J:
    def __init__(self, txt: str):
        self.v: C = None
        self.u: F = None
        self.txt = txt

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

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

class B:
    def __init__(self, txt: str):
        self.v: G = None
        self.s: E = None
        self.r: F = None
        self.txt = txt

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

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

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

class F:
    def __init__(self, txt: str):
        self.w: J = None
        self.v: A = None
        self.o: D = None
        self.t: B = None
        self.x: D = None
        self.q: A = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.o: J = None
        self.q: I = None
        self.z: D = None
        self.txt = txt

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

class J:
    def __init__(self, txt: str):
        self.v: C = None
        self.u: F = None
        self.txt = txt

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

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