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

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

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

class D:
    def __init__(self, txt: str):
        self.r: G = None
        self.s: F = None
        self.txt = txt

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

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

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

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

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

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

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

class D:
    def __init__(self, txt: str):
        self.r: G = None
        self.s: F = None
        self.txt = txt

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

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

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

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

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