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

class B:
    def __init__(self, txt: str):
        self.p: G = None
        self.v: D = None
        self.s: G = None
        self.txt = txt

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

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

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

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

class G:
    def __init__(self, txt: str):
        self.x: E = None
        self.u: E = None
        self.r: C = None
        self.s: F = None
        self.txt = txt

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

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

class B:
    def __init__(self, txt: str):
        self.p: G = None
        self.v: D = None
        self.s: G = None
        self.txt = txt

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

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

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

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

class G:
    def __init__(self, txt: str):
        self.x: E = None
        self.u: E = None
        self.r: C = None
        self.s: F = None
        self.txt = txt

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

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