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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def build_extension(self, ext):
 """ build clrmagic.dll using csc or mcs """

        if sys.platform == "win32":
            _clr_compiler = "C:\\Windows\\Microsoft.NET\\Framework\\v4.0.30319\\csc.exe"
        else:
            _clr_compiler = "mcs"
        cmd = [ 
            _clr_compiler,
            "/target:library",
            "clrmagic.cs"
        ]
        check_call(" ".join(cmd), shell=True)