Traceback (most recent call last):


 "<ipython-input-15-8ab0723181fb>", line 1, in <module>

df1.append(df2)


 "/home/andre/miniconda3/envs/pandas-dev/lib/python3.6/site-packages/pandas/core/frame.py", line 6211, in append

sort=sort)


 "/home/andre/miniconda3/envs/pandas-dev/lib/python3.6/site-packages/pandas/core/reshape/concat.py", line 226, in concat

return op.get_result()


 "/home/andre/miniconda3/envs/pandas-dev/lib/python3.6/site-packages/pandas/core/reshape/concat.py", line 423, in get_result

copy=self.copy)


 "/home/andre/miniconda3/envs/pandas-dev/lib/python3.6/site-packages/pandas/core/internals.py", line 5416, in concatenate_block_managers

elif is_uniform_join_units(join_units):


 "/home/andre/miniconda3/envs/pandas-dev/lib/python3.6/site-packages/pandas/core/internals.py", line 5440, in is_uniform_join_units

all(not ju.is_na or ju.block.is_extension for ju in join_units) and


 "/home/andre/miniconda3/envs/pandas-dev/lib/python3.6/site-packages/pandas/core/internals.py", line 5440, in <genexpr>

all(not ju.is_na or ju.block.is_extension for ju in join_units) and
AttributeError: 'NoneType' object has no attribute 'is_extension'

Traceback (most recent call last):


 "/usr/local/bin/pipenv", line 11, in <module>

sys.exit(cli())


 "/usr/local/lib/python2.7/site-packages/pipenv/vendor/click/core.py", line 722, in __call__

return self.main(*args, **kwargs)


 "/usr/local/lib/python2.7/site-packages/pipenv/vendor/click/core.py", line 697, in main

rv = self.invoke(ctx)


 "/usr/local/lib/python2.7/site-packages/pipenv/vendor/click/core.py", line 1043, in invoke

return Command.invoke(self, ctx)


 "/usr/local/lib/python2.7/site-packages/pipenv/vendor/click/core.py", line 895, in invoke

return ctx.invoke(self.callback, **ctx.params)


 "/usr/local/lib/python2.7/site-packages/pipenv/vendor/click/core.py", line 535, in invoke

return callback(*args, **kwargs)


 "/usr/local/lib/python2.7/site-packages/pipenv/vendor/click/decorators.py", line 17, in new_func

return f(get_current_context(), *args, **kwargs)


 "/usr/local/lib/python2.7/site-packages/pipenv/cli.py", line 713, in cli

loc = project.virtualenv_location


 "/usr/local/lib/python2.7/site-packages/pipenv/project.py", line 76, in virtualenv_location

c = delegator.run('pew dir "{0}"'.format(self.virtualenv_name))


 "/usr/local/lib/python2.7/site-packages/pipenv/project.py", line 57, in virtualenv_name

sanitized = re.sub(r'[ $`!*@"\\\r\n\t]', '_', self.name)[0:42]


 "/usr/local/lib/python2.7/site-packages/pipenv/project.py", line 32, in name

self._name = self.pipfile_location.split(os.sep)[-2]
AttributeError: 'NoneType' object has no attribute 'split'
