class A:
    def __init__(self, txt: str):
        self.r: B = None
        self.t: C = None
        self.s: B = None
        self.txt = txt

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

class C:
    def __init__(self, txt: str):
        self.v: A = None
        self.z: B = None
        self.o: F = None
        self.y: A = None
        self.txt = txt

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

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

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

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

d = A("d")
j = B("j")
b = C("b")
c = D("c")
a = E("a")
m = F("m")
f = G("f")
l = B("l")
k = B("k")

d.r = k
d.t = b
d.s = l
j.z = f
j.u = f
j.x = d
j.o = b
j.t = c
j.p = a
j.y = m
b.v = d
b.y = d
b.z = k
b.o = m
c.t = d
c.x = d
c.y = d
c.v = f
c.w = b
c.o = a
a.z = f
a.y = f
a.p = f
a.x = f
a.r = c
m.p = b
m.s = j
m.o = a
f.z = b
f.s = b
f.t = b
f.x = c
f.o = c
f.y = a
l.z = f
l.u = f
l.x = d
l.o = b
l.t = c
l.p = a
l.y = m
k.z = f
k.u = f
k.x = d
k.o = b
k.t = c
k.p = a
k.y = m
assert m.s.p.z.o.x.s.x.t.txt == "
class A:
    def __init__(self, txt: str):
        self.r: B = None
        self.t: C = None
        self.s: B = None
        self.txt = txt

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

class C:
    def __init__(self, txt: str):
        self.v: A = None
        self.z: B = None
        self.o: F = None
        self.y: A = None
        self.txt = txt

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

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

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

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

d = A("d")
j = B("j")
b = C("b")
c = D("c")
a = E("a")
m = F("m")
f = G("f")
l = B("l")
k = B("k")

d.r = k
d.t = b
d.s = l
j.z = f
j.u = f
j.x = d
j.o = b
j.t = c
j.p = a
j.y = m
b.v = d
b.y = d
b.z = k
b.o = m
c.t = d
c.x = d
c.y = d
c.v = f
c.w = b
c.o = a
a.z = f
a.y = f
a.p = f
a.x = f
a.r = c
m.p = b
m.s = j
m.o = a
f.z = b
f.s = b
f.t = b
f.x = c
f.o = c
f.y = a
l.z = f
l.u = f
l.x = d
l.o = b
l.t = c
l.p = a
l.y = m
k.z = f
k.u = f
k.x = d
k.o = b
k.t = c
k.p = a
k.y = m
assert m.s.p.z.o.x.s.x.t.txt == "b"