{
    "byline": null,
    "charset": "UTF-8",
    "dir": null,
    "excerpt": "Python applications will often use packages and modules that don\u2019t\ncome as part of the standard library.  Applications will sometimes\nneed a specific version of a library, because the application may\nrequire that a particular bug has been fixed or the application may be\nwritten using an obsolete version of the library\u2019s interface.",
    "lang": null,
    "length": 6617,
    "publishedTime": null,
    "siteName": null,
    "title": "12. Virtual Environments and Packages\u00b6"
}