How to download and setup chemdah
Open terminal and run command
                                            git clone https://github.com/TabooLib/chemdah.git
                                        
                                        git clone is used to create a copy or clone of chemdah repositories.
                                        You pass git clone a repository URL. it supports a few different network protocols and corresponding URL formats.
Also you may download zip file with chemdah https://github.com/TabooLib/chemdah/archive/master.zip
Or simply clone chemdah with SSH
                                            [email protected]:TabooLib/chemdah.git                                    
                                    If you have some problems with chemdah
You may open issue on chemdah support forum (system) here: https://github.com/TabooLib/chemdah/issuesSimilar to chemdah repositories
Here you may see chemdah alternatives and analogs
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