class A:
    def __init__(self, txt: str):
        self.y: E = None
        self.o: B = None
        self.q: B = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.y: F = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.q: F = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.v: D = None
        self.t: C = None
        self.z: D = None
        self.s: D = None
        self.p: D = None
        self.u: G = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.w: C = None
        self.p: D = None
        self.q: E = None
        self.o: C = None
        self.r: D = None
        self.t: C = None
        self.y: A = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.r: D = None
        self.v: B = None
        self.w: A = None
        self.u: F = None
        self.y: F = None
        self.z: F = None
        self.txt = txt

l = A("l")
a = B("a")
b = C("b")
i = D("i")
h = E("h")
j = F("j")
m = G("m")

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

class B:
    def __init__(self, txt: str):
        self.y: F = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.q: F = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.v: D = None
        self.t: C = None
        self.z: D = None
        self.s: D = None
        self.p: D = None
        self.u: G = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.w: C = None
        self.p: D = None
        self.q: E = None
        self.o: C = None
        self.r: D = None
        self.t: C = None
        self.y: A = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.r: D = None
        self.v: B = None
        self.w: A = None
        self.u: F = None
        self.y: F = None
        self.z: F = None
        self.txt = txt

l = A("l")
a = B("a")
b = C("b")
i = D("i")
h = E("h")
j = F("j")
m = G("m")

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