it's 99%:
i bolded what is missing ( closing ] at the end)

{
"pools" :
[

   {"pool_use_tls" : false, "keepalive" : false, "pool" : "xmr-eu1.nanopool.org:14444", "wallet" : "4Hm3YrYNgczRAP7jbGCZ7vA8XwbBR8DWMU7Bm9FKZqjxQXPBcwMP1kDbK3ntBSdt2c6TmLCPiMSXa39 uBiEBwkg4FUv8hdFDxqBKBCMUAT.SBR", "password" : "x"},
   {"pool_use_tls" : false, "keepalive" : false, "pool" : "xmr-eu2.nanopool.org:14444", "wallet" : "4Hm3YrYNgczRAP7jbGCZ7vA8XwbBR8DWMU7Bm9FKZqjxQXPBcwMP1kDbK3ntBSdt2c6TmLCPiMSXa39 uBiEBwkg4FUv8hdFDxqBKBCMUAT.SBR", "password" : "x"}
]
}