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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 is_dataframe(data):
 """ Checks whether the supplied data is of DataFrame type. """

    dd = None
    if 'dask' in sys.modules and 'pandas' in sys.modules:
        import dask.dataframe as dd
    return((pd is not None and isinstance(data, pd.DataFrame)) or
          (dd is not None and isinstance(data, dd.DataFrame)))