| Issue | Resolution | Reporter |
| Page 36. Possible Error | A code snippet on this page refers to the
Qtrac.Requirer class which isn't shown in the book but is
included in the source in the file Qtrac.py. According to
the reporter the __subclasshook__() method is incorrect.
Here's the reporter's version:
@classmethod
def __subclasshook__(Class, Subclass):
methods = set()
for Superclass in Class.__mro__:
if hasattr(Superclass, "required_methods"):
methods |= set(Superclass.required_methods)
if not methods:
return NotImplemented
attributes = collections.ChainMap(*(Superclass.__dict__
for Superclass in Subclass.__mro__))
if all(method in attributes for method in methods):
return True
return NotImplemented
|
Paolo Pastori |
| Page 111. Possible Error | The reporter claims that the def update
method on this page uses an incorrect expression to set
tippingPoint. The reporter says the code should be:
tippingPoint = round((model.value - model.minimum) * self.length /
(model.maximum - model.minimum))
| Paolo Pastori |
| Page 174. Error | In the paragraph beginning “After each
future...” delete the phrase “returns immediately and” from the second
sentence. (If you want an immediate return pass wait=False.) |
Hyunsok Oh |
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