val = 100

def fish(x):
    val = apple(x)
    return val + orange(val)

def apple(x):
    return x * 2

def orange(x):
    return x - 3

print fish(val)

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def double(x):
    return x + x

def quadruple_plus(y, extra):
    # Location B
    quad = double(double(y))
    # Location C
    return quad + extra

def foo(z, extra):
    # Location A
    return double(z) + quadruple_plus(z, extra)

x = 100
y = 3
print foo(y, x)

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