Terminal Failed to install packages Through Proxy network UBUNTU Solved

Edit /etc/sudoers file and add the following line

     Defaults env_keep = "http_proxy https_proxy ftp_proxy DISPLAY XAUTHORITY"

Open the file
    sudo nano /etc/sudoers

Find the "Defaults env_reset" and add after it

Save it and exit then set the proxy

For example

export http_proxy=http://192.168.40.136:7071/
export https_proxy=$http_proxy
export ftp_proxy=$http_proxy
export dns_proxy=$http_proxy
export rsync_proxy=$http_proxy
export no_proxy="localhost,127.0.0.1,localaddress,.localdomain.com"

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