var csc = new CSharpCodeProvider(new Dictionary<string, string>() { { "CompilerVersion", "v3.5" } });
	
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      extension=".vb"
      type="Microsoft.VisualBasic.VBCodeProvider, System, 
        Version=2.0.3600.0, Culture=neutral, 
        PublicKeyToken=b77a5c561934e089"
      compilerOptions="/optimize"
      warningLevel="1" >
      <providerOption
        name="CompilerVersion"
        value="v3.5" />
    </compiler>
    <compiler
      language="c#;cs;csharp"
      extension=".cs"
      type="Microsoft.CSharp.CSharpCodeProvider, System, 
        Version=2.0.3600.0, Culture=neutral, 
        PublicKeyToken=b77a5c561934e089"
      compilerOptions="/optimize"
      warningLevel="1" >
      <providerOption
        name="CompilerVersion"
        value="v3.5" />
    </compiler>
  </compilers>
</system.codedom>