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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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