Why does Python 2 use the \'u\' symbol for Unicode strings?

Unicode Strings and the 'u' Symbol

In the given code, you may have noticed the 'u' symbol preceding string values in the dictionary. This signifies that these strings are Unicode strings. Unicode is a character encoding standard that supports a vast range of characters, including those not found in the standard ASCII character set.

Python 2 and Unicode

In Python 2, Unicode strings are represented with the 'u' prefix. This is because in Python 2, strings are not Unicode by default. The 'u' prefix distinguishes Unicode strings from non-Unicode strings (which are known as 8-bit strings).

Creating Unicode Strings

There are several ways to create Unicode strings in Python 2:

• Using the 'u' prefix: u'foo'
• Using the unicode() function: unicode('foo')

Unicode Features

The main advantage of using Unicode strings is that they support a wide range of characters, including those from different languages and scripts. For example, the following Unicode string contains Russian characters:

<code class="python">val = u'Ознакомьтесь с документацией'</code>

When printed, this string displays the Russian text correctly.

Interoperability with Non-Unicode Strings

In Python 2, Unicode and non-Unicode strings are mostly interoperable. However, there are some differences to be aware of:

• Operations involving mixed Unicode and non-Unicode strings can result in Unicode errors.
• Comparisons between Unicode and non-Unicode strings may not always behave as expected.

Other String Symbols

Apart from the 'u' symbol, there are other symbols you may encounter when working with strings in Python:

• The 'r' symbol (for "raw") prevents backslashes from being interpreted as escape characters.
• The 'b' symbol indicates a byte string, which contains raw bytes instead of Unicode characters.

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