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

class B:
    def __init__(self, txt: str):
        self.r: G = None
        self.o: E = None
        self.u: G = None
        self.z: C = None
        self.y: C = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.w: E = None
        self.v: E = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.v: F = None
        self.x: E = None
        self.p: F = None
        self.w: D = None
        self.t: D = None
        self.q: B = None
        self.u: D = None
        self.txt = txt

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

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

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

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

class B:
    def __init__(self, txt: str):
        self.r: G = None
        self.o: E = None
        self.u: G = None
        self.z: C = None
        self.y: C = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.w: E = None
        self.v: E = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.v: F = None
        self.x: E = None
        self.p: F = None
        self.w: D = None
        self.t: D = None
        self.q: B = None
        self.u: D = None
        self.txt = txt

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

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

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

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