Add support for Python's new lazy import syntax (#4080)

* Add lazy keyword.

* Add a test case.

Author: ZeroIntensity

src/languages/python.js

@@ -58,7 +58,7 @@ export default {
 			},
 		},
 		'keyword':
-			/\b(?:_(?=\s*:)|and|as|assert|async|await|break|case|class|continue|def|del|elif|else|except|exec|finally|for|from|global|if|import|in|is|lambda|match|nonlocal|not|or|pass|print|raise|return|try|while|with|yield)\b/,
+			/\b(?:_(?=\s*:)|and|as|assert|async|await|break|case|class|continue|def|del|elif|else|except|exec|finally|for|from|global|if|import|in|is|lambda|match|nonlocal|not|or|pass|print|raise|return|try|while|with|yield|lazy)\b/,
 		'builtin':
 			/\b(?:__import__|abs|all|any|apply|ascii|basestring|bin|bool|buffer|bytearray|bytes|callable|chr|classmethod|cmp|coerce|compile|complex|delattr|dict|dir|divmod|enumerate|eval|execfile|file|filter|float|format|frozenset|getattr|globals|hasattr|hash|help|hex|id|input|int|intern|isinstance|issubclass|iter|len|list|locals|long|map|max|memoryview|min|next|object|oct|open|ord|pow|property|range|raw_input|reduce|reload|repr|reversed|round|set|setattr|slice|sorted|staticmethod|str|sum|super|tuple|type|unichr|unicode|vars|xrange|zip)\b/,
 		'boolean': /\b(?:False|None|True)\b/,

tests/languages/python/keyword_feature.test

@@ -9,7 +9,7 @@ pass print raise return
 try while with yield
 nonlocal
 and not or
-match case _:
+match case _: lazy
 
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@@ -25,7 +25,7 @@ match case _:
 	["keyword", "try"], ["keyword", "while"], ["keyword", "with"], ["keyword", "yield"],
 	["keyword", "nonlocal"],
 	["keyword", "and"], ["keyword", "not"], ["keyword", "or"],
-	["keyword", "match"], ["keyword", "case"], ["keyword", "_"], ["punctuation", ":"]
+	["keyword", "match"], ["keyword", "case"], ["keyword", "_"], ["punctuation", ":"], ["keyword", "lazy"]
 ]
 
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