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

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

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

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

class E:
    def __init__(self, txt: str):
        self.r: A = None
        self.o: E = None
        self.t: B = None
        self.v: D = None
        self.txt = txt

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

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

k = A("k")
i = B("i")
b = C("b")
j = D("j")
l = E("l")
n = F("n")
f = G("f")
c = C("c")
g = F("g")
m = E("m")

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

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

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

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

class E:
    def __init__(self, txt: str):
        self.r: A = None
        self.o: E = None
        self.t: B = None
        self.v: D = None
        self.txt = txt

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

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

k = A("k")
i = B("i")
b = C("b")
j = D("j")
l = E("l")
n = F("n")
f = G("f")
c = C("c")
g = F("g")
m = E("m")

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