# In []
# taking rows of 5 and 8
data_df = data_df_main.loc[(data_df_main['label'] == 5) | (data_df_main['label'] == 8)]
data_df
# In []
data_df = data_df.copy() # to prevent 'SettingwithCopyWarning' warning

data_df.loc[(data_df.label == 5),'label'] = 0 # convert all 5 labels to 0
data_df.loc[(data_df.label == 8),'label'] = 1 # convert all 8 labels to 1
data_df.index = np.arange(0, data_df.shape[0], 1) # newly indexing dataframe
data_df