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

class B:
    def __init__(self, txt: str):
        self.t: G = None
        self.q: E = None
        self.v: F = None
        self.r: C = None
        self.o: E = None
        self.x: F = None
        self.p: B = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.w: A = None
        self.q: A = None
        self.v: D = None
        self.txt = txt

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

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

class F:
    def __init__(self, txt: str):
        self.s: C = None
        self.x: D = None
        self.o: E = None
        self.u: B = None
        self.t: A = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.q: C = None
        self.t: A = None
        self.u: C = None
        self.txt = txt

k = A("k")
f = B("f")
d = C("d")
i = D("i")
b = E("b")
c = F("c")
h = G("h")
j = C("j")
l = B("l")

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

class B:
    def __init__(self, txt: str):
        self.t: G = None
        self.q: E = None
        self.v: F = None
        self.r: C = None
        self.o: E = None
        self.x: F = None
        self.p: B = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.w: A = None
        self.q: A = None
        self.v: D = None
        self.txt = txt

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

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

class F:
    def __init__(self, txt: str):
        self.s: C = None
        self.x: D = None
        self.o: E = None
        self.u: B = None
        self.t: A = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.q: C = None
        self.t: A = None
        self.u: C = None
        self.txt = txt

k = A("k")
f = B("f")
d = C("d")
i = D("i")
b = E("b")
c = F("c")
h = G("h")
j = C("j")
l = B("l")

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