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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 rename(**kwargs):
 """Rename one or more columns, leaving other columns unchanged Example usage: diamonds >> rename(new_name=old_name) """

  def rename_columns(df):
    column_assignments = {old_name_later._name: new_name
                          for new_name, old_name_later in kwargs.items()}
    return df.rename(columns=column_assignments)
  return rename_columns