Brython 3.7.5 performance compared to CPython

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Test Brython
(100 = CPython)
Code
simple assignment51
for i in range(1000000):
    a = 1
augmented assignment78
a = 0
for i in range(1000000):
    a += 1
simple assignment to float183
for i in range(1000000):
    a = 1.0
build dictionary407
for i in range(1000000):
    a = {0: 0}
build dictionary 293
d = {}
for i in range(100000):
    d[i] = i
set dictionary item107
a = {0: 0}
for i in range(1000000):
    a[0] = i
build set826
for i in range(1000000):
    a = {0, 2.7, "x"}
build list75
for i in range(1000000):
    a = [1, 2, 3]
set list item73
a = [0]
for i in range(1000000):
    a[0] = i
integer addition161
a, b, c = 1, 2, 3
for i in range(1000000):
    a + b + c
string addition75
a, b, c = 'a', 'b', 'c'
for i in range(1000000):
    a + b + c
cast int to string117
for i in range(100000):
    str(i)
create function without arguments271
for i in range(1000000):
    def f():
        pass
create function, single positional argument330
for i in range(1000000):
    def f(x):
        pass
create function, complex arguments624
for i in range(1000000):
    def f(x, y=1, *args, **kw):
        pass
function call789
def f(x):
    return x
for i in range(1000000):
    f(i)
function call, complex arguments823
def f(x, y=0, *args, **kw):
    return x
for i in range(100000):
    f(i, 5, 6, a=8)
create simple class409
for i in range(10000):
    class A:
        pass
create class with init430
for i in range(10000):
    class A:
        def __init__(self, x):
            self.x = x
create instance of simple class340
class A:
    pass

for i in range(1000000):
    A()
create instance of class with init537
class A:
    def __init__(self, x):
        self.x = x

for i in range(100000):
    A(i)
call instance method1603
class A:
    def __init__(self, x):
        self.x = x

    def f(self):
        return self.x

a = A(1)
for i in range(100000):
    a.f()