class A:
    def __init__(self, txt: str):
        self.o: E = None
        self.p: C = None
        self.z: D = None
        self.w: G = None
        self.v: D = None
        self.s: I = None
        self.x: C = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.z: D = None
        self.t: I = None
        self.s: F = None
        self.w: C = None
        self.p: F = None
        self.v: I = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.o: F = None
        self.txt = txt

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

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

class G:
    def __init__(self, txt: str):
        self.w: F = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.u: D = None
        self.r: F = None
        self.y: E = None
        self.w: F = None
        self.v: G = None
        self.q: A = None
        self.s: E = None
        self.o: D = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.x: H = None
        self.o: A = None
        self.t: F = None
        self.q: J = None
        self.txt = txt

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

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

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

class B:
    def __init__(self, txt: str):
        self.z: D = None
        self.t: I = None
        self.s: F = None
        self.w: C = None
        self.p: F = None
        self.v: I = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.o: F = None
        self.txt = txt

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

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

class G:
    def __init__(self, txt: str):
        self.w: F = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.u: D = None
        self.r: F = None
        self.y: E = None
        self.w: F = None
        self.v: G = None
        self.q: A = None
        self.s: E = None
        self.o: D = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.x: H = None
        self.o: A = None
        self.t: F = None
        self.q: J = None
        self.txt = txt

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

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

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