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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 validatefeatures(self,features):
 """Returns features in validated form, or raises an Exception. Mostly for internal use"""

        validatedfeatures = []
        for feature in features:
            if isinstance(feature, int) or isinstance(feature, float):
                validatedfeatures.append( str(feature) )
            elif self.delimiter in feature and not self.sklearn:
                raise ValueError("Feature contains delimiter: " + feature)
            elif self.sklearn and isinstance(feature, str): #then is sparse added together
                validatedfeatures.append(feature)
            else:
                validatedfeatures.append(feature)
        return validatedfeatures