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

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

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

class D:
    def __init__(self, txt: str):
        self.s: C = None
        self.x: I = None
        self.z: E = None
        self.q: H = None
        self.o: A = None
        self.w: J = None
        self.t: J = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.x: G = None
        self.y: D = None
        self.u: G = None
        self.o: H = None
        self.p: D = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.q: C = None
        self.y: G = None
        self.v: A = None
        self.w: D = None
        self.o: A = None
        self.s: B = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.u: A = None
        self.t: B = None
        self.x: D = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.s: B = None
        self.x: F = None
        self.u: A = None
        self.o: E = None
        self.v: E = None
        self.w: C = None
        self.y: E = None
        self.z: B = None
        self.txt = txt

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

class J:
    def __init__(self, txt: str):
        self.y: F = None
        self.x: E = None
        self.q: B = None
        self.p: F = None
        self.w: F = None
        self.z: A = None
        self.v: I = None
        self.t: I = None
        self.txt = txt

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

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

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

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

class D:
    def __init__(self, txt: str):
        self.s: C = None
        self.x: I = None
        self.z: E = None
        self.q: H = None
        self.o: A = None
        self.w: J = None
        self.t: J = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.x: G = None
        self.y: D = None
        self.u: G = None
        self.o: H = None
        self.p: D = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.q: C = None
        self.y: G = None
        self.v: A = None
        self.w: D = None
        self.o: A = None
        self.s: B = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.u: A = None
        self.t: B = None
        self.x: D = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.s: B = None
        self.x: F = None
        self.u: A = None
        self.o: E = None
        self.v: E = None
        self.w: C = None
        self.y: E = None
        self.z: B = None
        self.txt = txt

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

class J:
    def __init__(self, txt: str):
        self.y: F = None
        self.x: E = None
        self.q: B = None
        self.p: F = None
        self.w: F = None
        self.z: A = None
        self.v: I = None
        self.t: I = None
        self.txt = txt

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

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