Use of a print statement at module level¶
ID: py/print-during-import Kind: problem Security severity: Severity: recommendation Precision: high Tags: - quality - reliability - correctness Query suites: - python-code-quality.qls - python-security-and-quality.qls Click to see the query in the CodeQL repository
Using print statements in level scope may result in surprising output at import time. This in turn means that other code cannot safely import the module in question if the program may only write real output to standard out.
Recommendation¶
Replace the print statements with calls to some form of logging function or use the warnings module.
Example¶
In the example, importing the module may cause a message to be printed, which may interfere with the operation of the program.
try: import fast_system as system except ImportError: print ("Cannot import fast system, falling back on slow system") import slow_system as system #Fixed version import logging try: import fast_system as system except ImportError: logging.info("Cannot import fast system, falling back on slow system") import slow_system as system References¶
Python Language Reference: The print statement.
Python Standard Library: The print function.
Python tutorial: Modules.