class A:
    def __init__(self, txt: str):
        self.q: F = None
        self.x: I = None
        self.z: H = None
        self.u: C = None
        self.v: I = None
        self.s: C = None
        self.t: I = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.r: I = None
        self.p: I = None
        self.t: D = None
        self.z: H = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.r: H = None
        self.z: D = None
        self.y: E = None
        self.q: D = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.y: F = None
        self.r: F = None
        self.s: B = None
        self.t: C = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.x: C = None
        self.y: D = None
        self.q: G = None
        self.p: I = None
        self.w: C = None
        self.t: G = None
        self.z: D = None
        self.u: H = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.t: C = None
        self.q: H = None
        self.v: C = None
        self.s: A = None
        self.r: I = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.y: F = None
        self.t: B = None
        self.u: H = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.y: B = None
        self.v: E = None
        self.txt = txt

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

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

k.q = g
k.x = c
k.v = c
k.t = c
k.z = n
k.u = f
k.s = f
l.r = c
l.p = c
l.t = m
l.z = n
f.r = n
f.z = m
f.q = m
f.y = i
m.y = g
m.r = g
m.s = l
m.t = f
i.x = f
i.w = f
i.y = m
i.z = m
i.q = a
i.t = a
i.p = c
i.u = n
b.t = f
b.v = f
b.q = n
b.s = k
b.r = c
a.y = b
a.t = l
a.u = n
n.y = l
n.v = i
c.v = l
c.u = g
c.t = i
c.q = i
c.s = i
c.p = m
c.w = f
c.x = b
g.t = f
g.v = f
g.q = n
g.s = k
g.r = c
assert a.u.y.p.t.p.txt == "
class A:
    def __init__(self, txt: str):
        self.q: F = None
        self.x: I = None
        self.z: H = None
        self.u: C = None
        self.v: I = None
        self.s: C = None
        self.t: I = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.r: I = None
        self.p: I = None
        self.t: D = None
        self.z: H = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.r: H = None
        self.z: D = None
        self.y: E = None
        self.q: D = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.y: F = None
        self.r: F = None
        self.s: B = None
        self.t: C = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.x: C = None
        self.y: D = None
        self.q: G = None
        self.p: I = None
        self.w: C = None
        self.t: G = None
        self.z: D = None
        self.u: H = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.t: C = None
        self.q: H = None
        self.v: C = None
        self.s: A = None
        self.r: I = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.y: F = None
        self.t: B = None
        self.u: H = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.y: B = None
        self.v: E = None
        self.txt = txt

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

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

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