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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 check_case_sensitivity (self):
 """ Check if url and windows path name match cases else there might be problems when copying such files on web servers that are case sensitive. """

        if os.name != 'nt':
            return
        path = self.get_os_filename()
        realpath = get_nt_filename(path)
        if path != realpath:
            self.add_warning(_("The URL path %(path)r is not the same as the "
                            "system path %(realpath)r. You should always use "
                            "the system path in URLs.") % \
                            {"path": path, "realpath": realpath},
                               tag=WARN_FILE_SYSTEM_PATH)