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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(df, **kwargs):
 """Renames columns, where keyword argument values are the current names of columns and keys are the new names. Args: df (:obj:`pandas.DataFrame`):
 DataFrame passed in via `>>` pipe. Kwargs: **kwargs: key:value pairs where keys are new names for columns and values are current names of columns. """


    return df.rename(columns={v: k for k, v in kwargs.items()})