Python: Support for underscores in numbers (#3039)

Author: marvintensuan

Diff for: components/prism-python.js

@@ -54,7 +54,7 @@ Prism.languages.python = {
 	'keyword': /\b(?:and|as|assert|async|await|break|class|continue|def|del|elif|else|except|exec|finally|for|from|global|if|import|in|is|lambda|nonlocal|not|or|pass|print|raise|return|try|while|with|yield)\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(?:True|False|None)\b/,
-	'number': /(?:\b(?=\d)|\B(?=\.))(?:0[bo])?(?:(?:\d|0x[\da-f])[\da-f]*(?:\.\d*)?|\.\d+)(?:e[+-]?\d+)?j?\b/i,
+	'number': /\b0(?:b(?:_?[01])+|o(?:_?[0-7])+|x(?:_?[a-f0-9])+)\b|(?:\b\d+(?:_\d+)*(?:\.(?:\d+(?:_\d+)*)?)?|\B\.\d+(?:_\d+)*)(?:e[+-]?\d+(?:_\d+)*)?j?\b/i,
 	'operator': /[-+%=]=?|!=|\*\*?=?|\/\/?=?|<[<=>]?|>[=>]?|[&|^~]/,
 	'punctuation': /[{}[\];(),.:]/
 };

Diff for: components/prism-python.min.js

@@ -7,6 +7,14 @@
 0.3e-7
 4.8e+1
 42j
+0b_0001
+0b0_001
+0o_754
+0o7_540
+0x_BadFace
+0xBad_Face
+4_200
+4_200j
 
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@@ -19,7 +27,16 @@
 	["number", "2.1E10"],
 	["number", "0.3e-7"],
 	["number", "4.8e+1"],
-	["number", "42j"]
+	["number", "42j"],
+	["number", "0b_0001"],
+	["number", "0b0_001"],
+	["number", "0o_754"],
+	["number", "0o7_540"],
+	["number", "0x_BadFace"],
+	["number", "0xBad_Face"],
+	["number", "4_200"],
+	["number", "4_200j"]
+
 ]
 
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