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

class B:
    def __init__(self, txt: str):
        self.z: C = None
        self.x: E = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.x: F = None
        self.u: H = None
        self.v: C = None
        self.w: H = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.v: B = None
        self.o: I = None
        self.txt = txt

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

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

class H:
    def __init__(self, txt: str):
        self.t: F = None
        self.p: A = None
        self.u: E = None
        self.o: A = None
        self.txt = txt

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

class J:
    def __init__(self, txt: str):
        self.x: D = None
        self.v: H = None
        self.txt = txt

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

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

class B:
    def __init__(self, txt: str):
        self.z: C = None
        self.x: E = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.x: F = None
        self.u: H = None
        self.v: C = None
        self.w: H = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.v: B = None
        self.o: I = None
        self.txt = txt

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

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

class H:
    def __init__(self, txt: str):
        self.t: F = None
        self.p: A = None
        self.u: E = None
        self.o: A = None
        self.txt = txt

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

class J:
    def __init__(self, txt: str):
        self.x: D = None
        self.v: H = None
        self.txt = txt

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

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