Problem Formulation Given a tuple of elements. If you print the tuple to the shell using print((1, 2, 3)), the output is enclosed in parentheses like so: (1, 2, 3). But you want the list without brackets like so: 1, 2, 3. How to print the tuple without enclosing parentheses? Method 1: Unpacking The asterisk … Read more
Problem Formulation Given a dictionary of key value pairs in Python. If you print the dictionary to the shell using print({‘a’: 1, ‘b’: 2}), the output is enclosed in curly brackets (braces) like so: {‘a’: 1, ‘b’: 2}. But you want the dictionary without brackets like so: ‘a’: 1, ‘b’: 2. How to print the … Read more
Problem Formulation Given a list of elements. If you print the list to the shell using print([1, 2, 3]), the output is enclosed in square brackets like so: [1, 2, 3]. But you want the list without brackets like so: 1, 2, 3. How to print the list without enclosing brackets? Method 1: Unpacking The … Read more
Problem Formulation Given a file with name file.txt and the following content: hi finxters! 🙂 You created a Python script that reads the file line-by-line and prints each line to the shell like so: But the output unexpectedly adds an extra newline to each line so you obtain the following output on the Python shell: … Read more
Python’s print() function prints a string representation of any number of arguments to the standard output. It has many arguments such as the sep argument to set a custom separator string between the printed objects, the end argument to set a custom ending string, or the file argument to print a string into a file. … Read more
Problem Formulation Assuming you have the Python package manager pip installed in your operating system (Windows, Linux, macOS). How to check the version of a package with pip? Method 1: pip show To check which version of a given package is installed, use the pip show <your_package> command. For example, to check the version of … Read more
Problem Formulation Given a Python dictionary d, and a list of dictionary keys. How to best determine the list of values associated to the keys? Formally, for each key in the input list, you want to add d[key] to the list of values. Here’s a minimal example: # Input: d = {‘alice’: 18, ‘bob’: 24, … Read more
Problem Formulation Python has two ways to comment out a block of code: The hashtag symbol # tells the Python interpreter to ignore the rest of the line. To manually commenting out a block of code by inserting a hashtag symbol in front of every line is cumbersome. The multi-line string triple quotes ”’…”’ or … Read more
Today’s tutorial will introduce two slightly more advanced concepts of closures and decorators in Python. We’ll explain what they are, how each is defined, and where and how they will help in your coding. Nested Functions I’m sure you are all familiar with functions, and some of you may have used, or heard of, nested … Read more
The most idiomatic way to create a random integer in Python is the randint() function of the random module. Its two arguments start and end define the range of the generated integers. The return value is a random integer in the interval [start, end] including both interval boundaries. For example, randint(0, 9) returns an integer … Read more
A namespace is a filing system used by Python to track all the names given to objects when you write a program. When I first began trying to understand namespaces in Python, the tutorials I came across were confusing and less than helpful in their descriptions. Today I will take you on a logical and … Read more
To end a while loop prematurely in Python, press CTRL-C while your program is stuck in the loop. This will raise a KeyboardInterrupt error that terminates the whole program. To avoid termination, enclose the while loop in a try/except block and catch the KeyboardInterrupt. You can see the idea in the following code snippet: The … Read more