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

class B:
    def __init__(self, txt: str):
        self.r: E = None
        self.w: G = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.u: E = None
        self.p: B = None
        self.q: E = None
        self.r: D = None
        self.s: F = None
        self.w: G = None
        self.t: G = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.o: A = None
        self.w: B = None
        self.q: D = None
        self.s: D = None
        self.u: G = None
        self.txt = txt

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

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

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

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

class B:
    def __init__(self, txt: str):
        self.r: E = None
        self.w: G = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.u: E = None
        self.p: B = None
        self.q: E = None
        self.r: D = None
        self.s: F = None
        self.w: G = None
        self.t: G = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.o: A = None
        self.w: B = None
        self.q: D = None
        self.s: D = None
        self.u: G = None
        self.txt = txt

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

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

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

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