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This option controls how often warnings are output to stderr. Leave blank to default to one warning for each source line where it occurs. [-W]
Multiple options may be given; when a warning matches more than one option, the action for the last matching option is performed. Invalid options are ignored (though, a warning message is printed about invalid options when the first warning is issued).
The simplest form of argument is one of the following action strings:
- ignore - Ignore all warnings
- default - Explicitly request the default behaviour (printing each warning once per source line)
- all - Print a warning each time it occurs (this may generate many messages if a warning is triggered repeatedly for the same source line, such as inside a loop)
- module - Print each warning only the first time it occurs in each module
- once - Print each warning only the first time it occurs in the program.
- error - Raise an exception instead of printing a warning message.
The full form of argument is: Individual warnings filters are specified as a sequence of fields separated by colons: 'action:message:category:module:line'
For more information, please refer to the warnings module in the python documentation.
Warn about Python 3.x possible incompatibilities
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