Import issue in jupyter notebook

[spestushko]

Hello

I observed the following issue when trying to import ggplot in jupyter notebook:

ImportError                               Traceback (most recent call last)
<ipython-input-9-cae5702426bf> in <module>
      5 from pandas import Timestamp
      6 
----> 7 from ggplot import *

~/.virtualenvs/datascience/lib/python3.6/site-packages/ggplot/__init__.py in <module>
     18 
     19 from .geoms import geom_area, geom_blank, geom_boxplot, geom_line, geom_point, geom_jitter, geom_histogram, geom_density, geom_hline, geom_vline, geom_bar, geom_abline, geom_tile, geom_rect, geom_bin2d, geom_step, geom_text, geom_path, geom_ribbon, geom_now_its_art, geom_violin, geom_errorbar, geom_polygon
---> 20 from .stats import stat_smooth, stat_density
     21 
     22 from .facets import facet_wrap, facet_grid, Facet

~/.virtualenvs/datascience/lib/python3.6/site-packages/ggplot/stats/__init__.py in <module>
      1 from .stat_density import stat_density
----> 2 from .stat_smooth import stat_smooth

~/.virtualenvs/datascience/lib/python3.6/site-packages/ggplot/stats/stat_smooth.py in <module>
      3 
      4 from ..geoms.geom import geom
----> 5 from . import smoothers
      6 from ..utils import is_date
      7 

~/.virtualenvs/datascience/lib/python3.6/site-packages/ggplot/stats/smoothers.py in <module>
      2                         unicode_literals)
      3 import numpy as np
----> 4 from pandas.lib import Timestamp
      5 import pandas as pd
      6 import statsmodels.api as sm

ImportError: cannot import name 'Timestamp'

python -v: 3.6.2
macos mojave: 10.14