volver a muestrear pandas

In [101]: df.resample('1H').agg({'openbid': 'first', 
                                 'highbid': 'max', 
                                 'lowbid': 'min', 
                                 'closebid': 'last'})
Out[101]: 
                      lowbid  highbid  closebid  openbid
ctime                                                   
2015-09-30 23:00:00  1.11687  1.11712   1.11708    1.117
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