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

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

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

class D:
    def __init__(self, txt: str):
        self.o: D = None
        self.s: C = None
        self.u: E = None
        self.q: C = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.p: D = None
        self.s: A = None
        self.q: E = None
        self.u: D = None
        self.w: E = None
        self.y: A = None
        self.v: A = None
        self.txt = txt

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

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

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

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

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

class D:
    def __init__(self, txt: str):
        self.o: D = None
        self.s: C = None
        self.u: E = None
        self.q: C = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.p: D = None
        self.s: A = None
        self.q: E = None
        self.u: D = None
        self.w: E = None
        self.y: A = None
        self.v: A = None
        self.txt = txt

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

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

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