# \[ethereum\_ropsten\] ModuleNotFoundError: No module named 'rlp'
**URL:** https://community.blockcerts.org/t/ethereum-ropsten-modulenotfounderror-no-module-named-rlp/2754
**Category:** Technical
**Created:** [February 22, 2021, 9:29pm UTC](https://community.blockcerts.org/t/ethereum-ropsten-modulenotfounderror-no-module-named-rlp/2754 "2021-02-22T21:29:34Z")
**Posts on this page:** 5
**Page:** 1
### Author:  [@nitinb](https://community.blockcerts.org/u/nitinb)
#### Post date: [February 22, 2021, 9:29pm UTC](https://community.blockcerts.org/t/ethereum-ropsten-modulenotfounderror-no-module-named-rlp/2754/1 "2021-02-22T21:29:34Z")
## I am trying to issue certificate in ethereum ropsten testnet. But I am facing error-
(venv) bash-4.3# pwd
/cert-issuer
**(venv) bash-4.3# cert-issuer -c conf\_ethtest.ini**
WARNING - Your app is configured to skip the wifi check when the USB is plugged in. Read the documentation to ensure this is what you want, since this is less secure
INFO - This run will try to issue on the ethereum\_ropsten chain
Traceback (most recent call last):
File “/usr/bin/cert-issuer”, line 33, in
sys.exit(load\_entry\_point(‘cert-issuer==2.0.25’, ‘console\_scripts’, ‘cert-issuer’)())
File “/usr/lib/python3.6/site-packages/cert\_issuer/ **main**.py”, line 17, in cert\_issuer\_main
issue\_certificates.main(parsed\_config)
File “/usr/lib/python3.6/site-packages/cert\_issuer/issue\_certificates.py”, line 31, in main
from cert\_issuer.blockchain\_handlers import ethereum
File “/usr/lib/python3.6/site-packages/cert\_issuer/blockchain\_handlers/ethereum/ **init**.py”, line 9, in
from cert\_issuer.blockchain\_handlers.ethereum.signer import EthereumSigner
File “/usr/lib/python3.6/site-packages/cert\_issuer/blockchain\_handlers/ethereum/signer.py”, line 1, in
import rlp
**ModuleNotFoundError: No module named 'rlp’**
## But rlp is already installed. I checked using pip freeze
eth-hash==0.3.1
eth-typing==2.2.2
eth-utils==1.10.0
ethereum==2.3.1
…
**rlp==0.6.0**
…
rlp is already installed .
### (venv) bash-4.3# pip install rlp
Requirement already satisfied: rlp in /root/venv/lib/python3.6/site-packages (0.6.0)
### ethereum\_requirements.txt contains
coincurve==7.1.0
ethereum==2.3.1
### Following is the configuration file-
rlp\<1(venv) bash-4.3# cat conf\_ethtest.ini
issuing\_address = 0xe38eeef35c10e33d077cb4e5cf67bfaec3b26758
chain = ethereum\_ropsten
usb\_name=/cert-issuer/
key\_file=pk\_issuer.txt
unsigned\_certificates\_dir=/cert-issuer/data/unsigned\_certificates
blockchain\_certificates\_dir=/cert-issuer/data/blockchain\_certificates
work\_dir=/cert-issuer/work
no\_safe\_mode
# How can I get past this error?Please help I am stuck.
---
### Author:  [@nitinb](https://community.blockcerts.org/u/nitinb)
#### Post date: [February 23, 2021, 5:37pm UTC](https://community.blockcerts.org/t/ethereum-ropsten-modulenotfounderror-no-module-named-rlp/2754/2 "2021-02-23T17:37:28Z")
Guy can anyone please help in this.
@Taibah @JustNET JustN @dannysuarez @jackblock @yosuke @lemoustachiste Anyone?
I am struck here for couple of days .
I tried after adding scrypt, in the Docker file.
Mentioned by @JustNET
> [@No module named setuptools](https://community.blockcerts.org/t/no-module-named-setuptools/1383/9):
>
> Solved now. I had to run the following;
> sudo apt-get install build-essential libssl-dev python-dev
> sudo apt-get install -y scrypt
## but issue is still there.
My docker file looks like this -
(venv) bash-4.3# cat ../cert-issuer/Dockerfile
FROM seegno/bitcoind:0.13-alpine
MAINTAINER Kim Duffy “kimhd@mit.edu”
COPY . /cert-issuer
COPY conf\_regtest.ini /etc/cert-issuer/conf.ini
RUN apk add --update
bash
ca-certificates
curl
gcc
gmp-dev
libffi-dev
libressl-dev
linux-headers
make
musl-dev
python
python3
libssl-dev
build-essential
python-dev
python3-dev
scrypt
tar
g++
libxslt-dev
&& python3 -m ensurepip
&& pip3 install --upgrade pip setuptools
&& mkdir -p /etc/cert-issuer/data/unsigned\_certificates
&& mkdir /etc/cert-issuer/data/blockchain\_certificates
&& mkdir ~/.bitcoin
&& echo $‘rpcuser=foo\nrpcpassword=bar\nrpcport=8332\nregtest=1\nrelaypriority=0\nrpcallowip=127.0.0.1\nrpcconnect=127.0.0.1\n’ \> /root/.bitcoin/bitcoin.conf
&& pip3 install chainpoint\>=0.0.2
&& sed -i.bak s/==1.0b1/\>=1.0.2/g /usr/lib/python3._/site-packages/merkletools-1.0.2-py3._.egg-info/requires.txt
&& pip3 install /cert-issuer/.
&& rm -r /usr/lib/python\*/ensurepip
&& rm -rf /var/cache/apk/\*
&& rm -rf /root/.cache
ENTRYPOINT bitcoind -daemon && bash
---
### Author:  [@lemoustachiste](https://community.blockcerts.org/u/lemoustachiste)
#### Post date: [February 24, 2021, 10:17am UTC](https://community.blockcerts.org/t/ethereum-ropsten-modulenotfounderror-no-module-named-rlp/2754/3 "2021-02-24T10:17:24Z")
I’m sorry I’m not a Python expert, but this looks not directly related to cert-issuer.
@lparker do you have any idea maybe?
---
### Author:  [@nitinb](https://community.blockcerts.org/u/nitinb)
#### Post date: [February 25, 2021, 3:38pm UTC](https://community.blockcerts.org/t/ethereum-ropsten-modulenotfounderror-no-module-named-rlp/2754/4 "2021-02-25T15:38:09Z")
I am able to generate a certificate now.
### The problem was when i was running the issue command
**(venv) bash-4.3# cert-issuer -c conf\_ethtest.ini**
for some reason instead of considering the installed rlp in virtual environment , it was trying to look outside the virtual env.
I don’t know why this happened . but when i did pip install coincurve==7.1.0
ethereum==2.3.1 & rlp==0.6.0 outside venv , It ran and issued certificate.
I tried checking the path variable but it was already pointing to the venv location. So for the time being I installed the above 3 libs outside venv until anyone can help me point out the issue.
@lemoustachiste Thanks for your support.
---
### Author:  [@gilbertcane](https://community.blockcerts.org/u/gilbertcane)
#### Post date: [October 17, 2022, 1:57pm UTC](https://community.blockcerts.org/t/ethereum-ropsten-modulenotfounderror-no-module-named-rlp/2754/5 "2022-10-17T13:57:51Z")
To make it short, it means that you lacked some “dependencies” for the libraries you wanted to use. This is a common problem when installing python packages, mainly in windows. Before trying to use any kind of library, first it is suggested to look up whether it needs another library in python “family”.
The solution is to provide the python interpreter with the path-to-your-module/library. The simplest solution is to append that [python path](http://net-informations.com/python/intro/path.htm) to your sys.path list. In your notebook, first try:
```auto
import sys
sys.path.append('my/path/to/module/folder')
```
This isn’t a permanent change in sys.path, because when you log out, your environment is reset, so any variables you may have set are lost.
The better (and more permanent) way to solve this is to set your PYTHONPATH, which provides the interpreter with additional directories look in for python packages/modules.
`from BASH type: export PYTHONPATH=/path/to/new/folder:/another/path/...../`
#each path must be separated by a colon