Python troubleshooting

Here we collect some information and links that can help you troubleshoot your Python programs.

Error messages

When you see Python error messages for the first time usually you are shocked. So much information, so many cryptic messages…

Don’t worry! Here we’ll explain most of them. After you see several of them, you will be more familiar with them. You’ll see that they can be very useful.

Here is a list of some common Python error messages along with explanations and tips on how to fix them:

SyntaxError: This error occurs when there is a syntax mistake in your code, such as a missing parenthesis, colon, or an incorrect indentation level.

To fix this error, carefully review your code and correct the syntax issue.

NameError: This error is raised when a variable or function name is used before it is defined.

To fix this error, ensure that you have defined the variable or function before using it, or check for typos in the name.

TypeError: This error occurs when you try to perform an operation on an object of an incorrect data type, such as adding a string to a number.

To fix this error, make sure you are using the appropriate data types for the operation you are trying to perform.

ValueError: This error is raised when a function receives an argument of the correct data type but with an invalid value.

To fix this error, check the input values passed to the function and make sure they meet the required conditions.

IndexError: This error occurs when you try to access an index that is out of range for a list, tuple, or string.

To fix this error, ensure that your index is within the valid range for the data structure you are working with.

KeyError: This error is raised when you try to access a dictionary value using a key that does not exist in the dictionary.

To fix this error, ensure that the key you are using is present in the dictionary or use the dict.get() method to provide a default value if the key is not found.

AttributeError: This error occurs when you try to access an attribute or method that does not exist for a particular object.

To fix this error, check the object’s class definition and ensure that the attribute or method you are trying to access is defined.

ImportError: This error is raised when you try to import a module or package that cannot be found.

To fix this error, ensure that the module or package is installed and that you are using the correct name and case when importing.

ZeroDivisionError: This error occurs when you attempt to divide a number by zero.

To fix this error, add a check to ensure that the denominator is not zero before performing the division operation.

FileNotFoundError: This error is raised when you try to open a file that does not exist or is not accessible.

To fix this error, check that the file path is correct and that the file exists before attempting to open it.