class A:
    def __init__(self, txt: str):
        self.x: B = None
        self.s: H = None
        self.v: C = None
        self.z: G = None
        self.p: C = None
        self.y: I = None
        self.r: C = None
        self.w: C = None
        self.txt = txt

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

class C:
    def __init__(self, txt: str):
        self.x: G = None
        self.p: A = None
        self.r: H = None
        self.o: H = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.z: E = None
        self.t: H = None
        self.p: B = None
        self.o: G = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.r: H = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.p: H = None
        self.s: A = None
        self.z: G = None
        self.q: A = None
        self.y: E = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.t: G = None
        self.txt = txt

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

f = A("f")
b = B("b")
l = C("l")
c = D("c")
d = E("d")
m = F("m")
i = G("i")
n = H("n")
j = I("j")

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

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

class C:
    def __init__(self, txt: str):
        self.x: G = None
        self.p: A = None
        self.r: H = None
        self.o: H = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.z: E = None
        self.t: H = None
        self.p: B = None
        self.o: G = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.r: H = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.p: H = None
        self.s: A = None
        self.z: G = None
        self.q: A = None
        self.y: E = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.t: G = None
        self.txt = txt

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

f = A("f")
b = B("b")
l = C("l")
c = D("c")
d = E("d")
m = F("m")
i = G("i")
n = H("n")
j = I("j")

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