class A:
    def __init__(self, txt: str):
        self.q: C = None
        self.z: E = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.u: G = None
        self.y: G = None
        self.v: A = None
        self.p: G = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.o: G = None
        self.v: E = None
        self.q: D = None
        self.s: D = None
        self.z: D = None
        self.y: G = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.s: C = None
        self.t: B = None
        self.o: G = None
        self.v: F = None
        self.x: D = None
        self.p: B = None
        self.q: C = None
        self.txt = txt

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

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

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

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

class B:
    def __init__(self, txt: str):
        self.u: G = None
        self.y: G = None
        self.v: A = None
        self.p: G = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.o: G = None
        self.v: E = None
        self.q: D = None
        self.s: D = None
        self.z: D = None
        self.y: G = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.s: C = None
        self.t: B = None
        self.o: G = None
        self.v: F = None
        self.x: D = None
        self.p: B = None
        self.q: C = None
        self.txt = txt

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

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

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

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