
Traceback (most recent call last):


 "/conda/lib/python2.7/site-packages/conda/exceptions.py", line 616, in conda_exception_handler

return_value = func(*args, **kwargs)


 "/conda/lib/python2.7/site-packages/conda_env/cli/main_create.py", line 112, in execute

installer.install(prefix, pkg_specs, args, env)


 "/conda/lib/python2.7/site-packages/conda_env/installers/pip.py", line 8, in install

pip_cmd = pip_args(prefix) + ['install', ] + specs

TypeError: unsupported operand type(s) for +: 'NoneType' and 'list'

Traceback (most recent call last):


 "test2.py", line 6, in <module>

node1 - Edge(color="red", minlen=2.0) - node2


 "/Users/yu/anaconda2/envs/python3.7/lib/python3.7/site-packages/diagrams/__init__.py", line 447, in __sub__

return self.connect(other)


 "/Users/yu/anaconda2/envs/python3.7/lib/python3.7/site-packages/diagrams/__init__.py", line 493, in connect

return self.node.connect(other, self)


 "/Users/yu/anaconda2/envs/python3.7/lib/python3.7/site-packages/diagrams/__init__.py", line 385, in connect

self._diagram.connect(self, node, edge)


 "/Users/yu/anaconda2/envs/python3.7/lib/python3.7/site-packages/diagrams/__init__.py", line 168, in connect

self.dot.edge(node.hashid, node2.hashid, **edge.attrs)


 "/Users/yu/anaconda2/envs/python3.7/lib/python3.7/site-packages/graphviz/dot.py", line 146, in edge

attr_list = self._attr_list(label, attrs, _attributes)


 "/Users/yu/anaconda2/envs/python3.7/lib/python3.7/site-packages/graphviz/lang.py", line 126, in attr_list

content = a_list(label, kwargs, attributes)


 "/Users/yu/anaconda2/envs/python3.7/lib/python3.7/site-packages/graphviz/lang.py", line 100, in a_list

for k, v in tools.mapping_items(kwargs) if v is not None]


 "/Users/yu/anaconda2/envs/python3.7/lib/python3.7/site-packages/graphviz/lang.py", line 100, in <listcomp>

for k, v in tools.mapping_items(kwargs) if v is not None]


 "/Users/yu/anaconda2/envs/python3.7/lib/python3.7/site-packages/graphviz/lang.py", line 62, in quote

if is_html_string(identifier) and not isinstance(identifier, NoHtml):
TypeError: expected string or bytes-like object
