Don't use mutables as argument defaults in functions

[kanu]

https://github.com/veox/python3-krakenex/blob/master/krakenex/api.py#L151
When defining functions like this def query_private(self, method, req={}, conn = None): you share a single instance of the req dictionary for every call that uses the default of req.

def fn(x={}):
    return x

call1 = fn()
print(call1)
call1["a"] = "A"
call2 = fn()
print(call2)
print (call1 == call2)

If you want a fresh instance of an dictionary on every call of the function I suggest something like this.

def fn(x=None):
    if x is None:
        x = {}

Nevertheless I don't see a concrete problem raised by this in your code.

[veox]

Looks like sugar. Good point, though.

Some of this code is slated to become obsolete - see #11. No warning for that has been issued yet, since there hasn't been a release.

Will try to include that when time permits. Feel free to PR, too.

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EDIT: Oh, and thanks for taking a look. :)