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</o:shapelayout></xml><![endif]--></head><body lang=RU link=blue vlink=purple><div class=WordSection1><p class=MsoNormal style='margin-bottom:12.0pt;background:white'><span lang=EN-US style='font-size:10.0pt;font-family:"Courier New";color:black;mso-fareast-language:RU'># first: works fine<o:p></o:p></span></p><p class=MsoNormal style='margin-bottom:12.0pt;background:white'><span lang=EN-US style='font-size:10.0pt;font-family:"Courier New";color:black;mso-fareast-language:RU'>x = [</span><span lang=EN-US style='font-size:10.0pt;font-family:"Courier New";color:blue;mso-fareast-language:RU'>1</span><span lang=EN-US style='font-size:10.0pt;font-family:"Courier New";color:#CC7832;mso-fareast-language:RU'>, </span><span lang=EN-US style='font-size:10.0pt;font-family:"Courier New";color:blue;mso-fareast-language:RU'>2</span><span lang=EN-US style='font-size:10.0pt;font-family:"Courier New";color:#CC7832;mso-fareast-language:RU'>, </span><span lang=EN-US style='font-size:10.0pt;font-family:"Courier New";color:blue;mso-fareast-language:RU'>4</span><span lang=EN-US style='font-size:10.0pt;font-family:"Courier New";color:#CC7832;mso-fareast-language:RU'>, </span><span lang=EN-US style='font-size:10.0pt;font-family:"Courier New";color:blue;mso-fareast-language:RU'>2</span><span lang=EN-US style='font-size:10.0pt;font-family:"Courier New";color:#CC7832;mso-fareast-language:RU'>, </span><span lang=EN-US style='font-size:10.0pt;font-family:"Courier New";color:blue;mso-fareast-language:RU'>1</span><span lang=EN-US style='font-size:10.0pt;font-family:"Courier New";color:#CC7832;mso-fareast-language:RU'>, </span><span lang=EN-US style='font-size:10.0pt;font-family:"Courier New";color:blue;mso-fareast-language:RU'>3</span><span lang=EN-US style='font-size:10.0pt;font-family:"Courier New";color:black;mso-fareast-language:RU'>]<br>x = </span><span lang=EN-US style='font-size:10.0pt;font-family:"Courier New";color:navy;mso-fareast-language:RU'>list</span><span lang=EN-US style='font-size:10.0pt;font-family:"Courier New";color:black;mso-fareast-language:RU'>(</span><span lang=EN-US style='font-size:10.0pt;font-family:"Courier New";color:navy;mso-fareast-language:RU'>set</span><span lang=EN-US style='font-size:10.0pt;font-family:"Courier New";color:black;mso-fareast-language:RU'>(x))<br>x.sort()<br></span><span lang=EN-US style='font-size:10.0pt;font-family:"Courier New";color:navy;mso-fareast-language:RU'>print</span><span lang=EN-US style='font-size:10.0pt;font-family:"Courier New";color:black;mso-fareast-language:RU'>(x) </span><i><span lang=EN-US style='font-size:10.0pt;font-family:"Courier New";color:gray;mso-fareast-language:RU'># output: 1, 2, 3, 4<br><br></span></i><span lang=EN-US style='font-size:10.0pt;font-family:"Courier New";color:black;mso-fareast-language:RU'># second: why x became None ??<o:p></o:p></span></p><p class=MsoNormal style='margin-bottom:12.0pt;background:white'><span lang=EN-US style='font-size:10.0pt;font-family:"Courier New";color:black;mso-fareast-language:RU'>x = [</span><span lang=EN-US style='font-size:10.0pt;font-family:"Courier New";color:blue;mso-fareast-language:RU'>1</span><span lang=EN-US style='font-size:10.0pt;font-family:"Courier New";color:#CC7832;mso-fareast-language:RU'>, </span><span lang=EN-US style='font-size:10.0pt;font-family:"Courier New";color:blue;mso-fareast-language:RU'>2</span><span lang=EN-US style='font-size:10.0pt;font-family:"Courier New";color:#CC7832;mso-fareast-language:RU'>, </span><span lang=EN-US style='font-size:10.0pt;font-family:"Courier New";color:blue;mso-fareast-language:RU'>4</span><span lang=EN-US style='font-size:10.0pt;font-family:"Courier New";color:#CC7832;mso-fareast-language:RU'>, </span><span lang=EN-US style='font-size:10.0pt;font-family:"Courier New";color:blue;mso-fareast-language:RU'>2</span><span lang=EN-US style='font-size:10.0pt;font-family:"Courier New";color:#CC7832;mso-fareast-language:RU'>, </span><span lang=EN-US style='font-size:10.0pt;font-family:"Courier New";color:blue;mso-fareast-language:RU'>1</span><span lang=EN-US style='font-size:10.0pt;font-family:"Courier New";color:#CC7832;mso-fareast-language:RU'>, </span><span lang=EN-US style='font-size:10.0pt;font-family:"Courier New";color:blue;mso-fareast-language:RU'>3</span><span lang=EN-US style='font-size:10.0pt;font-family:"Courier New";color:black;mso-fareast-language:RU'>]<br>x = </span><span lang=EN-US style='font-size:10.0pt;font-family:"Courier New";color:navy;mso-fareast-language:RU'>list</span><span lang=EN-US style='font-size:10.0pt;font-family:"Courier New";color:black;mso-fareast-language:RU'>(</span><span lang=EN-US style='font-size:10.0pt;font-family:"Courier New";color:navy;mso-fareast-language:RU'>set</span><span lang=EN-US style='font-size:10.0pt;font-family:"Courier New";color:black;mso-fareast-language:RU'>(x)).sort()<br></span><span lang=EN-US style='font-size:10.0pt;font-family:"Courier New";color:navy;mso-fareast-language:RU'>print</span><span lang=EN-US style='font-size:10.0pt;font-family:"Courier New";color:black;mso-fareast-language:RU'>(x) </span><i><span lang=EN-US style='font-size:10.0pt;font-family:"Courier New";color:gray;mso-fareast-language:RU'># output: None<o:p></o:p></span></i></p><p class=MsoNormal style='margin-bottom:12.0pt;background:white'><span lang=EN-US style='font-size:10.0pt;font-family:"Courier New";mso-fareast-language:RU'>I know that sort() returns None, but I guess that it would be returned x that was sorted. Why so?<i><br><br></i></span><span lang=EN-US style='font-size:10.0pt;font-family:"Courier New";mso-fareast-language:RU'><o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p></div></body></html>