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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 remove_na(self, data, remove_na_how):
 """ Remove NAs from dataframe. Parameters data : pd.DataFrame() Dataframe to remove NAs from. remove_na_how : str Returns ------- pd.DataFrame() Dataframe with NAs removed. """

        data = data.dropna(how=remove_na_how)        
        return data