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

class B:
    def __init__(self, txt: str):
        self.p: A = None
        self.w: G = None
        self.txt = txt

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

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

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

class F:
    def __init__(self, txt: str):
        self.z: G = None
        self.v: D = None
        self.s: B = None
        self.y: D = None
        self.o: E = None
        self.u: I = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.x: D = None
        self.q: F = None
        self.r: D = None
        self.u: J = None
        self.s: D = None
        self.txt = txt

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

class J:
    def __init__(self, txt: str):
        self.v: A = None
        self.s: D = None
        self.u: E = None
        self.t: E = None
        self.x: H = None
        self.r: E = None
        self.txt = txt

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

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

class B:
    def __init__(self, txt: str):
        self.p: A = None
        self.w: G = None
        self.txt = txt

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

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

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

class F:
    def __init__(self, txt: str):
        self.z: G = None
        self.v: D = None
        self.s: B = None
        self.y: D = None
        self.o: E = None
        self.u: I = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.x: D = None
        self.q: F = None
        self.r: D = None
        self.u: J = None
        self.s: D = None
        self.txt = txt

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

class J:
    def __init__(self, txt: str):
        self.v: A = None
        self.s: D = None
        self.u: E = None
        self.t: E = None
        self.x: H = None
        self.r: E = None
        self.txt = txt

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

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