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

class B:
    def __init__(self, txt: str):
        self.y: F = None
        self.s: C = None
        self.w: A = None
        self.r: C = None
        self.v: G = None
        self.q: G = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.w: D = None
        self.y: G = None
        self.o: G = None
        self.txt = txt

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

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

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

class G:
    def __init__(self, txt: str):
        self.z: A = None
        self.s: D = None
        self.w: D = None
        self.txt = txt

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

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

class B:
    def __init__(self, txt: str):
        self.y: F = None
        self.s: C = None
        self.w: A = None
        self.r: C = None
        self.v: G = None
        self.q: G = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.w: D = None
        self.y: G = None
        self.o: G = None
        self.txt = txt

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

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

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

class G:
    def __init__(self, txt: str):
        self.z: A = None
        self.s: D = None
        self.w: D = None
        self.txt = txt

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

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