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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_environment(self, environment):
 """ Make sure the environment contains only strings (since putenv needs a string) """


        non_strings = []
        for (k,v) in environment.items():
            if not isinstance(v, basestring):
                non_strings.append(k)
        if non_strings:
            raise ValueError("The following environment variables are not strings: {}".format(", ".join(non_strings)))
        else:
            return True