prompt: We are currently solving the following issue within our repository. Here is the issue text:
  --- BEGIN ISSUE ---
  module 'netket' has no attribute 'MPI'
  With the merge #193 we have lost the MPI module 
  
  --- END ISSUE ---
  
  Below are some code segments, each from a relevant file. One or more of these files may contain bugs.
  --- BEGIN FILES ---
  Path: `netket/__init__.py`
  Content:
  ```
  1 # Copyright 2019 The Simons Foundation, Inc. - All Rights Reserved.
  2 #
  3 # Licensed under the Apache License, Version 2.0 (the "License");
  4 # you may not use this file except in compliance with the License.
  5 # You may obtain a copy of the License at
  6 #
  7 #    http://www.apache.org/licenses/LICENSE-2.0
  8 #
  9 # Unless required by applicable law or agreed to in writing, software
  10 # distributed under the License is distributed on an "AS IS" BASIS,
  11 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  12 # See the License for the specific language governing permissions and
  13 # limitations under the License.
  14 
  15 from __future__ import absolute_import
  16 from . import (
  17     _C_netket,
  18     dynamics,
  19     exact,
  20     graph,
  21     hilbert,
  22     layer,
  23     machine,
  24     operator,
  25     optimizer,
  26     output,
  27     sampler,
  28     stats,
  29     supervised,
  30     unsupervised,
  31     utils,
  32     variational,
  33 )
  34
  ```
  --- END FILES ---
  
  Please first localize the bug based on the issue statement, and then generate a patch according to the `git diff` format fenced by three backticks.
  
  Here is an example:
  
  ```diff
  diff --git a/examples/server_async.py b/examples/server_async.py
  --- a/examples/server_async.py
  +++ b/examples/server_async.py
  @@ -313,4 +313,4 @@
   
   
   if __name__ == "__main__":
  -    asyncio.run(run_async_server("."), debug=True)
  +    asyncio.run(run_async_server(), debug=True)
  diff --git a/examples/server_sync.py b/examples/server_sync.py
  --- a/examples/server_sync.py
  +++ b/examples/server_sync.py
  @@ -313,5 +313,5 @@
   
   
   if __name__ == "__main__":
  -    server = run_sync_server(".")
  +    server = run_sync_server()
       server.shutdown()
  
  ```
  
golden_diff: diff --git a/netket/__init__.py b/netket/__init__.py
  --- a/netket/__init__.py
  +++ b/netket/__init__.py
  @@ -31,3 +31,4 @@
       utils,
       variational,
   )
  +from ._C_netket import MPI, LookupReal, LookupComplex
  
verification_info: {"golden_diff": "diff --git a/netket/__init__.py b/netket/__init__.py\n--- a/netket/__init__.py\n+++ b/netket/__init__.py\n@@ -31,3 +31,4 @@\n     utils,\n     variational,\n )\n+from ._C_netket import MPI, LookupReal, LookupComplex\n", "issue": "module 'netket' has no attribute 'MPI'\nWith the merge #193 we have lost the MPI module \n", "before_files": [{"content": "# Copyright 2019 The Simons Foundation, Inc. - All Rights Reserved.\n#\n# Licensed under the Apache License, Version 2.0 (the \"License\");\n# you may not use this file except in compliance with the License.\n# You may obtain a copy of the License at\n#\n#    http://www.apache.org/licenses/LICENSE-2.0\n#\n# Unless required by applicable law or agreed to in writing, software\n# distributed under the License is distributed on an \"AS IS\" BASIS,\n# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.\n# See the License for the specific language governing permissions and\n# limitations under the License.\n\nfrom __future__ import absolute_import\nfrom . import (\n    _C_netket,\n    dynamics,\n    exact,\n    graph,\n    hilbert,\n    layer,\n    machine,\n    operator,\n    optimizer,\n    output,\n    sampler,\n    stats,\n    supervised,\n    unsupervised,\n    utils,\n    variational,\n)\n", "path": "netket/__init__.py"}], "after_files": [{"content": "# Copyright 2019 The Simons Foundation, Inc. - All Rights Reserved.\n#\n# Licensed under the Apache License, Version 2.0 (the \"License\");\n# you may not use this file except in compliance with the License.\n# You may obtain a copy of the License at\n#\n#    http://www.apache.org/licenses/LICENSE-2.0\n#\n# Unless required by applicable law or agreed to in writing, software\n# distributed under the License is distributed on an \"AS IS\" BASIS,\n# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.\n# See the License for the specific language governing permissions and\n# limitations under the License.\n\nfrom __future__ import absolute_import\nfrom . import (\n    _C_netket,\n    dynamics,\n    exact,\n    graph,\n    hilbert,\n    layer,\n    machine,\n    operator,\n    optimizer,\n    output,\n    sampler,\n    stats,\n    supervised,\n    unsupervised,\n    utils,\n    variational,\n)\nfrom ._C_netket import MPI, LookupReal, LookupComplex\n", "path": "netket/__init__.py"}]}