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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 argv_to_cmdline(argv):
 """ Convert a list of arguments to a single command line string. @type argv: list( str ) @param argv: List of argument strings. The first element is the program to execute. @rtype: str @return: Command line string. """

        cmdline = list()
        for token in argv:
            if not token:
                token = '""'
            else:
                if '"' in token:
                    token = token.replace('"', '\\"')
                if  ' ' in token  or \
                    '\t' in token or \
                    '\n' in token or \
                    '\r' in token:
                        token = '"%s"' % token
            cmdline.append(token)
        return ' '.join(cmdline)