class A:
    def __init__(self, txt: str):
        self.x: E = None
        self.p: G = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.y: D = None
        self.z: E = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.u: F = None
        self.r: D = None
        self.v: D = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.p: A = None
        self.w: H = None
        self.q: C = None
        self.v: F = None
        self.y: D = None
        self.x: D = None
        self.r: C = None
        self.z: B = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.o: I = None
        self.p: I = None
        self.u: A = None
        self.w: I = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.s: A = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.z: C = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.v: G = None
        self.q: G = None
        self.x: H = None
        self.y: F = None
        self.u: A = None
        self.p: C = None
        self.t: E = None
        self.s: H = None
        self.txt = txt

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

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

class B:
    def __init__(self, txt: str):
        self.y: D = None
        self.z: E = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.u: F = None
        self.r: D = None
        self.v: D = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.p: A = None
        self.w: H = None
        self.q: C = None
        self.v: F = None
        self.y: D = None
        self.x: D = None
        self.r: C = None
        self.z: B = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.o: I = None
        self.p: I = None
        self.u: A = None
        self.w: I = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.s: A = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.z: C = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.v: G = None
        self.q: G = None
        self.x: H = None
        self.y: F = None
        self.u: A = None
        self.p: C = None
        self.t: E = None
        self.s: H = None
        self.txt = txt

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

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