Python’s ImportError (ModuleNotFoundError) indicates that you tried to import a module that Python doesn’t find. It can usually be eliminated by adding a file named __init__.py to the directory and then adding this directory to $PYTHONPATH. If this file (__init__.py) is in the folder, change the position of the import in the file that is …
If you run the following code, you’ll experience a special ValueError: The output will be this error message: Try It Yourself in our interactive browser shell: Solution: Using the Numpy functions called logical_and() and logical_or() instead of Python’s logical operators (“and” and “or”) is the solution. Why does the ValueError occur at all? Many programmers …
You may know the following problem: You have an object’s attribute name as a string—say, you’ve read it from a file—and you want to access the attribute with the given name. But you cannot use the syntax object.”attribute” because the dot notation only allows for name-access like this: object.attribute. How do you resolve this problem? …
How to Access an Object Attribute Given the Attribute Name as a String? Read More »
Summary: Download a file over the web by using the following steps in Python. Import libary requests Define URL string Get file data from URL Store file data in file object on your computer Here’s how you can do this to download the Facebook Favicon (source): At the beginning of our struggle with web scraping, …
To test multiple variables x, y, z against a value v, use the set membership operation v in {x, y, z} that leverages the in keyword to check if the value v matches any value in the set {x, y, z}. The return value is a Boolean and the runtime complexity is O(1) to check …
Many beginner programmers have a problem with the so-called TypeError, they wonder what they are doing wrong. Here’s an example: Exercise: Run the script and reproduce the error! Study this article to learn how to fix it! This article will answer every question that beginners may ask about this topic. About The TypeError Before showing …
How to resolve “TypeError: can only concatenate str (not “int”) to str” in Python? Read More »
