class A:
    def __init__(self, txt: str):
        self.x: I = None
        self.t: B = None
        self.y: E = None
        self.z: I = None
        self.u: I = None
        self.q: B = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.w: A = None
        self.u: H = None
        self.z: G = None
        self.q: H = None
        self.p: C = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.u: B = None
        self.s: A = None
        self.r: B = None
        self.w: H = None
        self.o: I = None
        self.v: I = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.v: A = None
        self.x: G = None
        self.z: I = None
        self.w: H = None
        self.r: H = None
        self.q: I = None
        self.o: J = None
        self.p: I = None
        self.u: H = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.x: J = None
        self.y: H = None
        self.p: I = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.r: B = None
        self.p: B = None
        self.z: E = None
        self.t: I = None
        self.v: H = None
        self.s: E = None
        self.q: G = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.v: F = None
        self.s: E = None
        self.p: J = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.y: G = None
        self.r: J = None
        self.z: G = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.u: J = None
        self.y: C = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.z: B = None
        self.u: B = None
        self.txt = txt

k = A("k")
b = B("b")
f = C("f")
h = D("h")
g = E("g")
i = F("i")
m = G("m")
l = H("l")
c = I("c")
j = J("j")

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

class B:
    def __init__(self, txt: str):
        self.w: A = None
        self.u: H = None
        self.z: G = None
        self.q: H = None
        self.p: C = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.u: B = None
        self.s: A = None
        self.r: B = None
        self.w: H = None
        self.o: I = None
        self.v: I = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.v: A = None
        self.x: G = None
        self.z: I = None
        self.w: H = None
        self.r: H = None
        self.q: I = None
        self.o: J = None
        self.p: I = None
        self.u: H = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.x: J = None
        self.y: H = None
        self.p: I = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.r: B = None
        self.p: B = None
        self.z: E = None
        self.t: I = None
        self.v: H = None
        self.s: E = None
        self.q: G = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.v: F = None
        self.s: E = None
        self.p: J = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.y: G = None
        self.r: J = None
        self.z: G = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.u: J = None
        self.y: C = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.z: B = None
        self.u: B = None
        self.txt = txt

k = A("k")
b = B("b")
f = C("f")
h = D("h")
g = E("g")
i = F("i")
m = G("m")
l = H("l")
c = I("c")
j = J("j")

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