pd resample error

0.20.3
/Users/mona/computer_vision/tweets_debates/temporal_analysis.py:17: FutureWarning:
.resample() is now a deferred operation
You called rename(...) on this deferred object which materialized it into a dataframe
by implicitly taking the mean.  Use .resample(...).mean() instead
  .resample(FIVEMIN, on='Time')
Traceback (most recent call last):
  File "/Users/mona/computer_vision/tweets_debates/temporal_analysis.py", line 18, in <module>
    .rename('Tweets/5 min')
  File "/Users/mona/anaconda/lib/python3.6/site-packages/pandas/core/frame.py", line 2746, in rename
    **kwargs)
  File "/Users/mona/anaconda/lib/python3.6/site-packages/pandas/core/generic.py", line 727, in rename
    level=level)
  File "/Users/mona/anaconda/lib/python3.6/site-packages/pandas/core/internals.py", line 2853, in rename_axis
    obj.set_axis(axis, _transform_index(self.axes[axis], mapper, level))
  File "/Users/mona/anaconda/lib/python3.6/site-packages/pandas/core/internals.py", line 4755, in _transform_index
    items = [func(x) for x in index]
  File "/Users/mona/anaconda/lib/python3.6/site-packages/pandas/core/internals.py", line 4755, in <listcomp>
    items = [func(x) for x in index]
TypeError: 'str' object is not callable

Process finished with exit code 1