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Line terminator adds dot at the end of a line in npm test of Python code

I wanted to learn command line programming using Python.
I saw a to-do challenge on the internet and started to work on it by learning from the web. The challenge is to create a command line interface of a to-do app.
The challenge is titled CoronaSafe Engineering Fellowship Test Problem. Here is the challenge material on Google Drive: https://drive.google.com/drive/folders/1SyLcxnEBNRecIyFAuL5kZqSg8Dw4xnTG?usp=sharing
and there is a GitHub project at https://github.com/nseadlc-2020/package-todo-cli-task/
In the README.md I was instructed to create symbolic link for the batch file todo.bat with the name todo. Now, my first condition is that, when the symbolic link is called from the command prompt without any arguments, it must print some usage tips for the program. Finally, I have to use the npm test command to test the execution.
At the very beginning I got this trouble, whenever I use a print statement, I see a dot • at the end of every string which ends with a new line. For instance,
import sys
import random
args = sys.argv[1:]
if len(args) == 0:
print('Usage :-', end='\n')
print('$ ./todo help # Show usage', end='')
The above statements when executed without arguments gives the output,
Usage :-.
$ ./todo help # Show usage
Here, I noticed that for the first print statement ends with a newline, the string ends with what looks like a middle dot (•). Whereas, for the second print statement since I override the end parameter with an empty string, no newline character was output, and so the dot is not printed. See the screen shot:
What's wrong, and how can I pass the test? My program does not print a middle dot at all.

The problem seems to be squarely inside the todo.test.js file.
In brief, Windows and Unix-like platforms have different line ending conventions (printing a line in Windows adds two control characters at the end, whilst on Unix-like systems only one is printed) and it looks like the test suite is only prepared to cope with results from Unix-like systems.
Try forcing your Python to only print Unix line feeds, or switch to a free Unix-like system for running the tests.
Alternatively, rename todo.test.js and replace it with a copy with DOS line feeds. In many Windows text editors, you should be able to simply open the file as a Unix text file, then "Save As..." and select Windows text file (maybe select "ANSI" if it offers that, though the term is horribly wrong and they should know better); see e.g. Windows command to convert Unix line endings? for many alternative solutions (many of which vividly illustrate some of the other issues with Windows; proceed with caution).
This seems to be a known issue, as noted in the README.md you shared: https://github.com/nseadlc-2020/package-todo-cli-task/issues/12 (though it imprecisely labels this as "newline UTF encoding issues"; the problem has nothing to do with UTF-8 or UTF-16).
See also the proposed duplicate Line endings (also known as Newlines) in JS strings

I had exactly the same problem.
I replaced:
print(variable_name) # Or print("Your text here")
With:
sys.stdout.buffer.write(variable_name.encode('utf-8')) # To sys.stdout.buffer.write("Your text here".encode('utf-8'))
Now it worked fine in windows.

First write your help string like this
help_string='Usage :-\n$ ./task add 2 hello world # Add a new item with priority 2 and text "hello world" to the list\n$ ./task ls # Show incomplete priority list items sorted by priority in ascending order\n$ ./task del INDEX # Delete the incomplete item with the given index\n$ ./task done INDEX # Mark the incomplete item with the given index as complete\n$ ./task help # Show usage\n$ ./task report # Statistics'
Then print it on the console using
sys.stdout.buffer.write(help_string.encode('utf8'))
This problem occurs due to differences in encoding type of windows and npm tests. Also make sure to avoid any spaces after or before "\n".

Why have multiple prints,when python prints can incorporate new line without having to declare separately, follow example below:
print("Usage :- \n$ ./todo help #Show usage")
Output:
Usage :-
$ ./todo help #Show usage

Advanced input in python

I want to receive some information from a user in a next way:
My score is of 10 - is already printed
Between 'is' and 'of' there is an empty place for user's input so he doesn't enter his information at the end( if using simple input() ) but in the middle. While user is entering some information it appears between 'is' and 'of'
Is there any possible way to do it?

One way to get something close to what you want is if you terminal supports ANSI escape codes:
x = input("My score is \x1b[s of 10\x1b[u")
\x1b is the escape character. Neither escape character is dipsplayed on the screen; instead, they introduce byte sequences that the terminal interprets as an instruction of some kind. ESC[s tells the terminal to remember where the cursor is at the moment. ESC[u tells the terminal to move the cursor to the last-remembered position.
(The rectangle is the cursor in an unfocused window.)
Using a library that abstracts away the exact terminal you are using is preferable, but this gives you an idea of how such libraries interact with your terminal: it's all just bytes written to standard output.

If you use console then consider importing curses library. It works on both linux and windows. Download it for windows from http://www.lfd.uci.edu/~gohlke/pythonlibs/#curses
With this library you have a total control over console. Here is the answer to your question.
How to input a word in ncurses screen?

Entering multiple lines of code to be run later at the Python REPL [duplicate]

This question already has answers here:
Python, writing multi line code in IDLE
(7 answers)
Closed 6 years ago.
I just picked up a basic book today on programming. The coding language is Python and I have only been trying this out for a few hours but I'm already stuck, because I can't figure out how to write multiple lines of code. For example, when I write print("one") and then hit enter, it just runs it and prints the word, one. How can I have it print the word, one, and then the word, two, on the line below it? Also, when I hit tab it just moves over 4 spaces, or so. I can't figure out how to have it not run the first command, and just give me '>>>' on the next line. So I guess what I'm asking is: What keystrokes do I need to use to get something like:
>>> print("one")
>>> print("two")
Thanks so much!
(Sorry for such a basic question, but I'm totally confused on this one.)

The Python REPL automatically executes each command as soon as it is completely typed in. This is why it is called a "read-eval-print loop". It accepts one input, evaluates it, and then prints the result.
If you want to execute two complete commands at once, you can put a semicolon between them, like this:
print("one"); print("two")
I said "completely typed in" above, because some commands inherently require multiple lines, so Python must accept several lines of input before the command is "completely typed in". Three types of command work like this: flow-control commands (def, while, if, for, etc., which apply to several indented lines below them), multiline expressions (calculations inside parentheses or brackets), or statements that use a backslash (\) at the end of the line to indicate that it is continued on the next line. So if you type in any of the blocks below, Python will wait until the block is completely finished before evaluating it.
if 1 + 1 == 2:
print "True"
else:
print "False"
print(
1 + 1
)
print \
1 + 1
You could also combine these two strategies and type something like this:
print("one"); \
print("two")
Python will wait for both commands to be typed and then run them both at once. But I've never seen anyone write code that way.
Alternatively, you could type several commands together in a different text editor, and then paste them into the Python REPL, e.g., copy and paste the following into your REPL (but you will get results printed between the commands):
print("one")
print("two")
Alternatively, you can probably get almost exactly the behavior you were originally expecting by using a different interface to Python. The IPython Notebook is a good choice, or you could try the Spyder or PyCharm editors, which let you select a few lines of code and run them.
Or, if you have a longer script that you want to run all at once, the best option is to type it up in a text file (e.g., script.py), and then tell python to run it, e.g., type python script.py from a system command prompt (not the Python interpreter), or press F5 in the IDLE editor.

One thing you may want to try is writing your code in a file, say learning.py, and then running that file on the command line with python learning.py.

The best way to get better support for multi line commands in python with a "console" feel is to use ipython qtconsole, or Jupyter qtconsole as its now called: http://jupyter.org/qtconsole/stable/. When using qtconsole, hitting Ctrl-Enter will delay the command from running even if it's not a complex block. You can keep hitting Ctrl-Enter as many times as you want, and then hit Enter to run them all. Hitting up arrow will then bring up the whole block again to edit, cleanly indented unlike the regular ipython console.
Note: this is not ipython notebook, nor the regular ipython console, but a separate thing from either using the same kernel. The qtconsole has some other nice things like better syntax highlighting and inline plotting compared to the terminal.

Python system argument reading '&'

I want to pass url to my python via the console and then do the appropriate tasks. many of the links contain the character '&' in the link. python interprets that as ending the argument this however is not what I want. here is a sample of the code
import sys
external_id = sys.argv[1].encode("utf-8")
print external_id
And when I run the following:
python graph.py 2%60&7
I get:
2%60
How do I make python interpret the '&' as nothing more than another character in the url?

This is not python, it's bash. You need to escape it:
python graph.py 2%60\&7

Quoting this answer:
The & informs the shell to put the command in the background.
Python never receives that character because the shell takes care of it, thus this isn't an issue of Python. You can also wrap 2%60&7 with quotes to make it work
me#pc:~$ python3 script.py '2%60&7'
b'2%60&7'
Sometimes escaping & is a lot harder than doing this.

python IDLE shell appears not to handle some escapes correctly

For example \b backspace prints as quad (shown as [] in example below). But \n newline is Ok.
>>> print 'abc\bd'
abc[]d
>>> print 'abc\nd'
abc
d
Im running under Vista (pro), python 2.7
Ive tried googling this issue generally and in SO and cant find anything relevant, which seems odd and makes me wonder if theres some setting or other may be wrong in my setup. Not sure what to look for.

What am I doing wrong or what should I be looking for?
Is it reasonable to expect backspace, specifically, to work?
No, IDLE does not support backspace, nor carriage-return, nor formfeed, nor ANSI escape sequences.
You are expecting \b to move the cursor one cell to the left in IDLE's interactive shell window. It doesn't do that. IDLE does not support cursor addressing in its shell window, with the exception of newline and tab.