🌐 Mailman 3 July 2022 - Tutor - python.org

Unittest question
by Albert-Jan Roskam Aug. 3, 2022

Aug. 3, 2022

Hi, I am trying to run the same unittests against two different implementations of a module. Both use C functions in a dll, but one uses ctypes and the other that I just wrote uses CFFI. How can do this nicely? I don't understand why the code below won't run both flavours of tests. It says "Ran 1 test", I expected two! Any ideas? Thanks! Albert-Jan import unittest class MyTest(unittest.TestCase): def __init__(self, *args, **kwargs): self.implementation = kwargs.pop("implementation", None) if self.implementation == "CFFI": import my_module_CFFI as xs else: import my_module as xs super().__init__(*args, **kwargs) def test_impl(self): print(self.implementation) self.assertEqual(self.implementation, "") if __name__ == "__main__": suite = unittest.TestSuite() suite.addTests(MyTest(implementation="CFFI")) suite.addTests(MyTest(implementation="ctypes")) runner = unittest.TextTestRunner(verbosity=3) runner.run(suite) ###Output: AssertionError: None != '' -------------------- >> begin captured stdout << --------------------- None --------------------- >> end captured stdout << ---------------------- ----------------------------------------------------------------------

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POSIT and QUARTO
by avi.e.gross＠gmail.com July 29, 2022

July 29, 2022

This is not a question. Just a fairly short comment about changes that may impact some Python users. I have long used both R and python to do things but had to use different development environments. The company formerly called RSTUDIO has been increasingly supporting python as well as R and now has been renamed to POSIT, presumably by adding a P for Python and keeping some letter from STudIO: https://www.r-bloggers.com/2022/07/posit-why-rstudio-is-changing-its-name/?u tm_source=phpList <https://www.r-bloggers.com/2022/07/posit-why-rstudio-is-changing-its-name/? utm_source=phpList&utm_medium=email&utm_campaign=R-bloggers-daily&utm_conten t=HTML> &utm_medium=email&utm_campaign=R-bloggers-daily&utm_content=HTML I mention this as I have already been doing some python work in RSTUDIO as well as anaconda and for small bits in IDLE and even in a CYGWIN environment and my machine is a tad confused at the multiple downloads of various versions of python. Also, I have been using tools to make live documents that run code and interleave it with text and the new company also supports a sort of vastly improved and merged version of a product that will now also work with python and other languages called QUARTO that some might be interested in. https://www.r-bloggers.com/2022/07/announcing-quarto-a-new-scientific-and-te chnical-publishing-system/?utm_source=phpList <https://www.r-bloggers.com/2022/07/announcing-quarto-a-new-scientific-and-t echnical-publishing-system/?utm_source=phpList&utm_medium=email&utm_campaign =R-bloggers-daily&utm_content=HTML> &utm_medium=email&utm_campaign=R-bloggers-daily&utm_content=HTML I have no personal connection with the company except as a happy user for many years who has been interested much more broadly than their initial product and will happily use the abilities they provide that let me mix and match what I do in an assortment of languages. Time for me to revisit Julia and Javascript that are now supported. I am NOT saying there is anything wrong with python, just a new option on how to work with python in a nice well-considered GUI that many already have found very useful. In many fields of use, many programmers and projects often choose among various programming languages and environments so you often end up having to be, in a sense, multilingual and multicultural. So it can be nice to work toward an environment where many people can be comfortable and even work together while remaining somewhat unique. The above is an example I have used to write documents that incorporate functionality as in use R to read in a file, convert it and save another file while producing some statistics in the text, then in the same document, have a snippet of python open that output file and do more and show it in the same document, as an example.

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Building dictionary from large txt file
by bobx ander July 27, 2022

July 27, 2022

Hi all, I'm trying to build a dictionary from a rather large file of following format after it has being read into a list(excerpt from start of list below) -------- Atomic Number = 1 Atomic Symbol = H Mass Number = 1 Relative Atomic Mass = 1.00782503223(9) Isotopic Composition = 0.999885(70) Standard Atomic Weight = [1.00784,1.00811] Notes = m -------- My goal is to extract the content into a dictionary that displays each unique triplet as indicated below {'H1': {'Z': 1,'A': 1,'m': 1.00782503223}, 'D2': {'Z': 1,'A': 2,'m': 2.01410177812} ...} etc My code that I have attempted is as follows: filename='ex.txt' afile=open(filename,'r') #opens the file content=afile.readlines() afile.close() isotope_data={'Z':0,'A':0,'m':0}#start to create subdictionary for each case of atoms with its unique keys and values for line in content: data=line.strip().split() if len(data)<1: pass elif data[0]=="Atomic" and data[1]=="Number": atomic_number=data[3] elif data[0]=="Mass" and data[1]=="Number": mass_number=data[3] elif data[0]=="Relative" and data[1]=="Atomic" and data[2]=="Mass": relative_atomic_mass=data[4] isotope_data['Z']=atomic_number isotope_data['A']=mass_number isotope_data['A']=relative_atomic_mass isotope_data the output from the programme is only {'Z': '118', 'A': '295', 'm': '295.21624(69#)'} I seem to be owerwriting each dictionary and ends up with the above result.Somehow i think I have to put the assigment of the key,value pairs elsewhere. I have tried directly below the elif statements also,but that did not work. Any hints or ideas Regards Bob

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Volunteer teacher
by trent shipley July 26, 2022

July 26, 2022

I've volunteered to do some informal Python teaching. What are some useful online resources and tutorials? What are some good, introductory books--whether ebooks or dead tree. I'm thinking of something very reader friendly, like the "teach yourself in 24 hours", or "for dummies series", but with good exercises. Has anyone used https://exercism.org/tracks/python? I've had good luck with the four JavaScript exercises I did, but I did one Scala exercise and the grader was broken (I confirmed it with a live mentor.) Trent

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teaching for purpose
by avi.e.gross＠gmail.com July 26, 2022

July 26, 2022

The recent discussion inspires me to open a new thread. It is about teaching a topic like python or kinds of programming it supports and doing it for a purpose in a way that does not overwhelm students but helps them understand the motivation and use of features. The recent topic was OOP and my thought was in several directions. One was bottom-up. Show what the world was like when you had individual variables only (meaning memory locations of sorts) and then some sort of array data structure was added so you can ask for var[5] and then if you wanted to store info about a group of say employees, you had one array for each attribute like name, salary, age. So a user could be identified as name[5] and salary[5] and age[5]. Then show what a pain it was to say fire a user or move them elsewhere without remembering to make changes all over the place. So you show the invention of structures like the C struct and how they now hold an employee together. Then you show how functions that operate on structs had to know what it was in order to be effective and general and that enhancing a struct to contain additional member functions and other features like inheritance, could lead to a concept where an object was central. Yes, there are more rungs on this ladder but this in enough for my purpose. The other way is to work more from top-down. Show them some complex network they all use and say this could not easily be build all at once, or efficiently, if it was not seen as parts and then parts within parts, with some parts re-used as needed. At the level of the programming language, the parts can be made somewhat smart and with goals if designed well. If you want to be able to process a container holding many kinds of parts, you may want each part to know how to do several things to itself so if you want all parts to be able to print some version of what they contain, you want to say object.printYourSelf() and each will do it their own way. You may want to invent protocols and insist that any object that wishes to be considered a member of this protocol, must implement the methods needed by the protocol and thus you can pass a collection of such objects to anything that wants the protocol to be used without worrying about errors if the wrong kind of object is there too. Again, I hope you get the idea. You can lead up to objects from basics or lead down as you deconstruct. Of course there are many other ways. I mention this because I personally find some features almost meaningless without the right context. Consider any GUI such as a browser where events seem to happen asynchronously depending on movements of the mouse, clicks, key-presses, and even events coming in from outside. Various parts of the program are not RUN in a deterministic manner but must pop into being, do a few things, and go away till needed again. In a sense, you set event listeners and attach bits of code such as functions or perhaps a method call for any object. In such an environment, all kinds of things get interesting and choices for implementation that do things in what may seem odd or indirect ways, suddenly may make some sense. So imagine first building an almost empty object that holds nothing and has a very few methods. Why would anyone want this? A while later you show how to make one and then more objects that inherit from the same object but BECAUSE they share a base, they have something in common, including in some languages the ability to be in a collection that insists everything be the SAME. Then you show how an object can be made easier and faster if it is only a bit different than another or by combining several others. At some point you want to make sure the students get the ideas behind it, not just some silly localized syntax useful only in that language. Once you have an idea of purpose, you may show them that others had similar purposes in mind but chose other ideas. Take the five or more ways python allows formatting text. As soon as you realize they are all variants with some similarities in purpose, you can more easily classify them and not struggle so much as to why anyone would do this. At least that is how my mind works. What I find helpful in motivating using objects when they really are NOT NEEDED is when it is explained that part of the purpose was to make a set of tools that work well together. Modules in python like sklearn stopped looking weird after I got that. I mean you can easily make functions for yourself (well, maybe not easily) that implement taking some data and return N clusters that are mostly closer within each cluster to some centroid than to other clusters. So why ask the user to set a variable to a new object of some sort, then repeatably ask the object to do things to itself like accept data or add to existing data, set various internal attributes like values telling it to be fast or accurate or which technique to use, or to transform the data by normalizing it some way, and run analyses and supply aspects of what it came up with or predict now new data would be transformed by the internal model? This does not, at first, seem necessary or at all useful. But consider how this scales up if say you want to analyze many files of data and do some comparisons. Each file can be held by it's own object and the objects can be kept in something like a list or matrix and can be used almost interchangeably with other objects that implement very different ways to analyze the data if they all take the same overall set of commands, as appropriate. All may be called, say, with new data, and asked to predict results based on previous learning steps. The point in all the above, which may easily be dismissed by the volume, is that I think part of learning is a mix of ideas in the abstract as well as some really concrete programming along the lines of prototyping. Learning Object Oriented Programming in the abstract may seem like a good idea, albeit implementations vary greatly. But knowing WHY some people developed those ideas and what they were meant to improve or handle, . I shudder sometimes when a functional programming person tries to sell me on using closures to retain values and so on, until I realize that in a sense, it overlaps object-oriented programming. Or does it?

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Error while connecting to SQL Server using Python
by Sachit Murarka July 23, 2022

July 23, 2022

Hello Users, Facing below error while using pyodbc to connect to SQL Server. conn = pyodbc.connect( pyodbc.Error: ('01000', "[01000] [unixODBC][Driver Manager]Can't open lib 'ODBC Driver 17 for SQL Server' : file not found (0) (SQLDriverConnect)") Can anyone pls suggest what could be done? Kind Regards, Sachit Murarka

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PermissionError: [WinError 32]
by Sagar Ahire July 21, 2022

July 21, 2022

Hello sir, I am getting below error while I install “pip install sasl” in cmd Error: PermissionError: [WinError 32] The process cannot access the file because it is being used by another process: 'C:\\Users\\SAGAR~1.AHI\\AppData\\Local\\Temp\\tmpxlfme666' I tried multiple things to resolve it but no luck, below is the list I tried Uninstall python and re-install Uninstall python and re-install with other directory folder Delete the temp folder 'C:\\Users\\SAGAR~1.AHI\\AppData\\Local\\Temp\\” Net Stop http and net start http in command prompt (getting error to stop http) Any help to resolve this will be greatly appreciated. Thank you Sagar Ahire

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WinError 32
by Ahire, Sagar July 21, 2022

July 21, 2022

Hello sir, I am getting below error while I install "pip install sasl" in cmd Error: PermissionError: [WinError 32] The process cannot access the file because it is being used by another process: 'C:\\Users\\SAGAR~1.AHI\\AppData\\Local\\Temp\\tmpxlfme666' I tried multiple things to resolve it but no luck, below is the list I tried 1. Uninstall python and re-install 2. Uninstall python and re-install with other directory folder 3. Delete the temp folder 'C:\\Users\\SAGAR~1.AHI\\AppData\\Local\\Temp\\" 4. Net Stop http and net start http in command prompt (getting error to stop http) Any help to resolve this will be greatly appreciated. Thank you Sagar Ahire ________________________________ This message (including any attachments) contains confidential and/or privileged information. It is intended for a specific individual and purpose and is protected by law. If you are not the intended recipient, please notify the sender immediately and delete this message. Any disclosure, copying, or distribution of this message, or the taking of any action based on it, is strictly prohibited. Asurion_Internal_Use_Only

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Need help installing a program on my computer using python (Bruker2nifti)
by Siddharth Satishchandran July 21, 2022

July 21, 2022

Hi I am a new user to Python. I am interested in installing a program on Python (Bruker2nifti). I am having trouble writing out the appropriate code to install the program. I know pip install bruker is needed but it is not working on my console. I would like to know the correct code I need to install the program. I can provide the GitHub if needed. -Sidd

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Ways of removing consequtive duplicates from a list
by Manprit Singh July 18, 2022

July 18, 2022

Dear Sir , I was just doing an experiment of removing consecutive duplicates from a list . Did it in the following ways and it all worked . Just need to know which one should be preferred ? which one is more good ? lst = [2, 2, 3, 3, 3, 2, 2, 5, 5, 6, 3, 3, 3, 3] # Ways of removing consequtive duplicates [ele for i, ele in enumerate(lst) if i==0 or ele != lst[i-1]] [2, 3, 2, 5, 6, 3] val = object() [(val := ele) for ele in lst if ele != val] [2, 3, 2, 5, 6, 3] import itertools [val for val, grp in itertools.groupby(lst)] [2, 3, 2, 5, 6, 3] Is there anything else more efficient ? Regards Manprit Singh

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