Handling Errors
As we get more familiar with the Python programming language, we run into errors and exceptions. These are complaints that Python makes when it doesn't understand what you want it to do. Everyone runs into these issues, so it is a good habit to read and understand them. Here are some common errors that we might run into when printing strings:
print "Mismatched quotes will cause a SyntaxError'
print Without quotes will cause a NameError
If the quotes are mismatched Python will notice this and inform you that your code has an error in its syntax because the line ended (called an
EOL) before the double-quote that was supposed to close the string appeared. The program will abruptly stop running with the following message:
SyntaxError: EOL while scanning a string literal
This means that a string wasn't closed, or wasn't closed with the same quote-character that started it.
Another issue you might run into is attempting to create a string without quotes at all. Python treats words not in quotes as commands, like the
printstatement. If it fails to recognize these words as defined (in Python or by your program elsewhere) Python will complain the code has a NameError. This means that Python found what it thinks is a command, but doesn't know what it means because it's not defined anywhere.
EXERCISE
We've written two
print statements that will raise errors. One has mismatched quotes and the other has no quotes at all.
Fix the two print statements to successfully debug the program!
Hint !
A print statement should start with the word
print and then should have the message inside matching quote marks.
print 'This is a good print statement'
Double quotes are also fine:
print "This is also a good print statement"
Script.py
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