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

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

class C:
    def __init__(self, txt: str):
        self.t: D = None
        self.s: D = None
        self.p: E = None
        self.v: F = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.o: B = None
        self.t: C = None
        self.r: F = None
        self.q: D = None
        self.txt = txt

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

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

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

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

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

class C:
    def __init__(self, txt: str):
        self.t: D = None
        self.s: D = None
        self.p: E = None
        self.v: F = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.o: B = None
        self.t: C = None
        self.r: F = None
        self.q: D = None
        self.txt = txt

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

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

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

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