title: Pandas rename & reindex: ValueError
body: <pre><code>def Transformation_To_UpdateNex(df):
     s = 'TERM-ID,NAME,QUALIFIER,FACET1_ID,FACET2_ID,FACET3_ID,FACET4_ID,GROUP1_ID,GROUP2_ID,GROUP3_ID,GROUP4_ID,IS_VALID,IS_SELLABLE,IS_PRIMARY,IS_BRANCHABLE,HAS_RULES,FOR_SUGGESTION,IS_SAVED,S_NEG,SCORE,GOOGLE_SV,CPC,SINGULARTEXT,SING_PLU_VORGABE'
     df_Import = pd.DataFrame(columns = s.split(','))
     d = {'TERMID':'TERM-ID', 'NAMECHANGE':'NAME', 'TYP':'QUALIFIER'}
     df_Import = df.rename(columns = d).reindex(columns=df_Import.columns)
  
     df_Import.to_csv("Update.csv", sep=";", index = False, encoding = "ISO-8859-1")
  
  
  ValueError: cannot reindex from a duplicate axis
  </code></pre>
  
  <p>I am trying to take values from a filled Dataframe and transfer these values keeping the same structure to my new Dataframe (<em>empty one described first in the code</em>). 
  Any ideas how to solve the value error? </p>