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

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

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

class D:
    def __init__(self, txt: str):
        self.w: C = None
        self.y: G = None
        self.u: G = None
        self.v: E = None
        self.o: D = None
        self.r: G = None
        self.s: G = None
        self.z: E = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.s: B = None
        self.w: G = None
        self.y: C = None
        self.p: D = None
        self.x: C = None
        self.txt = txt

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

class G:
    def __init__(self, txt: str):
        self.o: E = None
        self.w: H = None
        self.y: B = None
        self.t: H = None
        self.q: G = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.p: D = None
        self.r: C = None
        self.y: A = None
        self.txt = txt

a = A("a")
d = B("d")
k = C("k")
f = D("f")
l = E("l")
h = F("h")
n = G("n")
c = H("c")
m = G("m")
i = D("i")

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

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

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

class D:
    def __init__(self, txt: str):
        self.w: C = None
        self.y: G = None
        self.u: G = None
        self.v: E = None
        self.o: D = None
        self.r: G = None
        self.s: G = None
        self.z: E = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.s: B = None
        self.w: G = None
        self.y: C = None
        self.p: D = None
        self.x: C = None
        self.txt = txt

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

class G:
    def __init__(self, txt: str):
        self.o: E = None
        self.w: H = None
        self.y: B = None
        self.t: H = None
        self.q: G = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.p: D = None
        self.r: C = None
        self.y: A = None
        self.txt = txt

a = A("a")
d = B("d")
k = C("k")
f = D("f")
l = E("l")
h = F("h")
n = G("n")
c = H("c")
m = G("m")
i = D("i")

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