# If you'd like to omit non-matching lines from the result; add ';d' to the end of the expression.
sed -E 's/"union[^}]+}\s*,//gm;t' <<< " json<- '{\"open_issues\":0,\"union\":{\"avatar_url\":\"https://secure.gravatar.com/avatar/ed73cf7f24c091318e507d167c7b3456?d=https://a248.e.akamai.net/assets.mashups.com%2Fimages%2Fgravatars%2Fgravatar-orgs.png\",\"gravatar_id\":\"ed73cf7f24c091318e507d167c7b3456\",\"id\":1556245,\"login\":\"Toolpark\",\"url\":\"https://api.mashups.com/users/Toolpark\"},\"owner\":{\"avatar_url\":\"https://secure.gravatar.com/avatar/ed73cf7f24c091318e507d167c7b3456?d=https://a248.e.akamai.net/assets.mashups.com%2Fimages%2Fgravatars%2Fgravatar-orgs.png\",\"gravatar_id\":\"ed73cf7f24c091318e507d167c7b3456\",\"id\":1556245,\"login\":\"Toolpark\",\"url\":\"https://api.mashups.com/users/Toolpark\"},\"private\":false,\"pushed_at\":\"2012-07-12T11:43:31Z\",\"size\":964,\"ssh_url\":\"vit@mashups.com:Toolpark/irma.vit\",\"svn_url\":\"https://mashups.com/Toolpark/irma\",\"updated_at\":\"2012-07-12T11:43:31Z\",\"url\":\"https://api.mashups.com/repos/Toolpark/irma\",\"watchers\":2}'
"
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for SED, please visit: https://www.gnu.org/software/sed/manual/html_node/The-_0022s_0022-Command.html