Не могу запустить app.py (import dash) с текущей версией python 3.7

Не могу запустить app.py (import dash) с текущей версией python 3.7

     pip install dash==1.10.0

    conda install -c conda-forge dash

python app.py

Traceback (most recent call last):
      File "app.py", line 1, in <module>
        import dash
      File "//anaconda3/lib/python3.7/site-packages/dash/__init__.py", line 1, in <module>
        from .dash import Dash, no_update  # noqa: F401
      File "//anaconda3/lib/python3.7/site-packages/dash/dash.py", line 23, in <module>
        import plotly
      File "//anaconda3/lib/python3.7/site-packages/plotly/__init__.py", line 30, in <module>
        from plotly import (
      File "//anaconda3/lib/python3.7/site-packages/plotly/graph_objs/__init__.py", line 101462, in <module>
        import ipywidgets
      File "//anaconda3/lib/python3.7/site-packages/ipywidgets/__init__.py", line 25, in <module>
        from .widgets import *
      File "//anaconda3/lib/python3.7/site-packages/ipywidgets/widgets/__init__.py", line 4, in <module>
        from .widget import Widget, CallbackDispatcher, register, widget_serialization
      File "//anaconda3/lib/python3.7/site-packages/ipywidgets/widgets/widget.py", line 15, in <module>
        from ipykernel.comm import Comm
      File "//anaconda3/lib/python3.7/site-packages/ipykernel/comm/__init__.py", line 1, in <module>
        from .manager import *
      File "//anaconda3/lib/python3.7/site-packages/ipykernel/comm/manager.py", line 15, in <module>
        from .comm import Comm
      File "//anaconda3/lib/python3.7/site-packages/ipykernel/comm/comm.py", line 9, in <module>
        from ipykernel.kernelbase import Kernel
      File "//anaconda3/lib/python3.7/site-packages/ipykernel/kernelbase.py", line 19, in <module>
        from jupyter_client.session import utcnow as now
      File "//anaconda3/lib/python3.7/site-packages/jupyter_client/session.py", line 61, in <module>
        from jupyter_client.jsonutil import extract_dates, squash_dates, date_default
      File "//anaconda3/lib/python3.7/site-packages/jupyter_client/jsonutil.py", line 11, in <module>
        from dateutil.parser import parse as _dateutil_parse
      File "//anaconda3/lib/python3.7/site-packages/dateutil/parser.py", line 158
        l.append("%s=%s" % (attr, `value`))
                                  ^
    SyntaxError: invalid syntax