class A:
    def __init__(self, txt: str):
        self.z: E = None
        self.t: F = None
        self.v: D = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.z: G = None
        self.o: C = None
        self.y: D = None
        self.u: B = None
        self.t: G = None
        self.r: C = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.r: F = None
        self.o: B = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.o: E = None
        self.x: G = None
        self.u: E = None
        self.z: F = None
        self.s: B = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.q: G = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.q: B = None
        self.o: C = None
        self.r: C = None
        self.s: F = None
        self.u: D = None
        self.x: F = None
        self.txt = txt

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

g = A("g")
h = B("h")
c = C("c")
a = D("a")
l = E("l")
b = F("b")
m = G("m")
k = B("k")
j = B("j")
e = F("e")

g.z = l
g.t = b
g.v = a
h.z = m
h.t = m
h.o = c
h.r = c
h.y = a
h.u = k
c.r = e
c.o = k
a.o = l
a.u = l
a.x = m
a.z = b
a.s = j
l.q = m
b.q = j
b.o = c
b.r = c
b.s = e
b.x = e
b.u = a
m.y = g
m.z = l
m.x = a
k.z = m
k.t = m
k.o = c
k.r = c
k.y = a
k.u = j
j.z = m
j.t = m
j.o = c
j.r = c
j.y = a
j.u = h
e.q = k
e.o = c
e.r = c
e.s = b
e.x = b
e.u = a
assert m.x.x.x.o.txt == "
class A:
    def __init__(self, txt: str):
        self.z: E = None
        self.t: F = None
        self.v: D = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.z: G = None
        self.o: C = None
        self.y: D = None
        self.u: B = None
        self.t: G = None
        self.r: C = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.r: F = None
        self.o: B = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.o: E = None
        self.x: G = None
        self.u: E = None
        self.z: F = None
        self.s: B = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.q: G = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.q: B = None
        self.o: C = None
        self.r: C = None
        self.s: F = None
        self.u: D = None
        self.x: F = None
        self.txt = txt

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

g = A("g")
h = B("h")
c = C("c")
a = D("a")
l = E("l")
b = F("b")
m = G("m")
k = B("k")
j = B("j")
e = F("e")

g.z = l
g.t = b
g.v = a
h.z = m
h.t = m
h.o = c
h.r = c
h.y = a
h.u = k
c.r = e
c.o = k
a.o = l
a.u = l
a.x = m
a.z = b
a.s = j
l.q = m
b.q = j
b.o = c
b.r = c
b.s = e
b.x = e
b.u = a
m.y = g
m.z = l
m.x = a
k.z = m
k.t = m
k.o = c
k.r = c
k.y = a
k.u = j
j.z = m
j.t = m
j.o = c
j.r = c
j.y = a
j.u = h
e.q = k
e.o = c
e.r = c
e.s = b
e.x = b
e.u = a
assert m.x.x.x.o.txt == "l"