[FIXED] Which encoding is used for strings in Python 2.x?

Issue

What is the default encoding used for encoding strings in python 2.x? I've read that there are two possible ways to declare a string.

string = 'this is a string'
unicode_string = u'this is a unicode string'

The second string is in Unicode. What is the encoding of the first string?

Solution

As per Python default/implicit string encodings and conversions (reciting its Py2 part concisely, to minimize duplication):

There are actually multiple independent "default" string encodings in Python 2, used by different parts of its functionality.

• Parsing the code and string literals:

  • str from a literal -- will contain raw bytes from the file, no transcoding is done
  • unicode from a literal -- the bytes from the file are decode'd with the file's "source encoding" which defaults to ascii
  • with unicode_literals future, all literals in the file are treated as Unicode literals

• Transcoding/type conversion:

  • str<->unicode type conversion and encode/decode w/o arguments are done with sys.getdefaultencoding()
    • which is ascii almost always, so any national characters will cause a UnicodeError
  • str can only be decode'd and unicode -- encode'd. Trying otherwise will involve an implicit type conversion (with the aforementioned result)

• I/O, including printing:

  • unicode -- encode'd with <file>.encoding if set, otherwise implicitly converted to str (with the aforementioned result)
  • str -- raw bytes are written to the stream, no transcoding is done. For national characters, a terminal will show different glyphs depending on its locale settings.

Answered By - ivan_pozdeev