installing graph-tool


I'm new to both graph-tool and Ubuntu, which I'm installing it on (as a
virtual machine on my Windows 10 computer).

I've downloaded graph-tool 2.27 in my 'downloads' folder, and then followed
the install instructions at
Installation via package managers

However, this produces some error messages. Do I need to locate some or all
of the files I downloaded onto a specific location on my virtual machine?

Here's the output I get:

VirtualBox:/etc/apt$ sudo apt-get update

[sudo] password:

Hit:1 bionic InRelease

Get:2 bionic-security InRelease [83.2 kB]

Get:3 bionic-updates InRelease [88.7 kB]

Get:4 bionic-backports InRelease [74.6

Ign:5 raring InRelease

Err:6 raring Release

  404 Not Found [IP: 80]

Get:7 bionic-updates/main amd64 Packages
[351 kB]

Get:8 bionic-updates/main i386 Packages
[315 kB]

Get:9 bionic-updates/main amd64 DEP-11
Metadata [146 kB]

Get:10 bionic-updates/main DEP-11 48x48
Icons [39.1 kB]

Get:11 bionic-updates/main DEP-11 64x64
Icons [73.9 kB]

Get:12 bionic-updates/universe amd64
Packages [206 kB]

Get:13 bionic-updates/universe i386
Packages [206 kB]

Get:14 bionic-updates/universe amd64
DEP-11 Metadata [183 kB]

Get:15 bionic-updates/universe DEP-11
48x48 Icons [168 kB]

Get:16 bionic-updates/universe DEP-11
64x64 Icons [277 kB]

Get:17 bionic-updates/multiverse amd64
DEP-11 Metadata [2,468 B]

Get:18 bionic-backports/universe amd64
DEP-11 Metadata [5,100 B]

Reading package lists... Done

E: The repository ' raring Release'
does not have a Release file.

N: Updating from such a repository can't be done securely, and is therefore
disabled by default.

N: See apt-secure(8) manpage for repository creation and user configuration

VirtualBox:/etc/apt$ sudo apt-get install python-graph-tool

Reading package lists... Done

Building dependency tree

Reading state information... Done

E: Unable to locate package python-graph-tool

Any idea what is going wrong here?

attachment.html (5.98 KB)

You seem to be using the 'bionic' release, but you are trying to access the
'raring' repository for graph-tool. You should use 'bionic' instead.