A far as I can tell it was due to me running "python-light", installed the full python3 on a external usb as suggested and that fixed it.

Copied the output from installing python3, in case someone wants to dig into what the cause might be.

root@Omega-225A:/# opkg install python3 Installing python3 (3.4.3-2) to root... Downloading http://downloads.openwrt.org/chaos_calmer/15.05/ar71xx/generic/packages/packages/python3_3.4.3-2_ar71xx.ipk. Installing python3-light (3.4.3-2) to root... Downloading http://downloads.openwrt.org/chaos_calmer/15.05/ar71xx/generic/packages/packages/python3-light_3.4.3-2_ar71xx.ipk. Installing python3-base (3.4.3-2) to root... Downloading http://downloads.openwrt.org/chaos_calmer/15.05/ar71xx/generic/packages/packages/python3-base_3.4.3-2_ar71xx.ipk. Installing libffi (3.0.13-1) to root... Downloading http://downloads.openwrt.org/chaos_calmer/15.05/ar71xx/generic/packages/packages/libffi_3.0.13-1_ar71xx.ipk. Installing libbz2 (1.0.6-2) to root... Downloading http://downloads.openwrt.org/chaos_calmer/15.05/ar71xx/generic/packages/base/libbz2_1.0.6-2_ar71xx.ipk. Installing python3-asyncio (3.4.3-2) to root... Downloading http://downloads.openwrt.org/chaos_calmer/15.05/ar71xx/generic/packages/packages/python3-asyncio_3.4.3-2_ar71xx.ipk. Installing python3-codecs (3.4.3-2) to root... Downloading http://downloads.openwrt.org/chaos_calmer/15.05/ar71xx/generic/packages/packages/python3-codecs_3.4.3-2_ar71xx.ipk. Installing python3-ctypes (3.4.3-2) to root... Downloading http://downloads.openwrt.org/chaos_calmer/15.05/ar71xx/generic/packages/packages/python3-ctypes_3.4.3-2_ar71xx.ipk. Installing python3-dbm (3.4.3-2) to root... Downloading http://downloads.openwrt.org/chaos_calmer/15.05/ar71xx/generic/packages/packages/python3-dbm_3.4.3-2_ar71xx.ipk. Installing libdb47 (4.7.25.4.NC-4.1) to root... Downloading http://downloads.openwrt.org/chaos_calmer/15.05/ar71xx/generic/packages/packages/libdb47_4.7.25.4.NC-4.1_ar71xx.ipk. Installing libxml2 (2.9.2-3) to root... Downloading http://downloads.openwrt.org/chaos_calmer/15.05/ar71xx/generic/packages/packages/libxml2_2.9.2-3_ar71xx.ipk. Installing python3-decimal (3.4.3-2) to root... Downloading http://downloads.openwrt.org/chaos_calmer/15.05/ar71xx/generic/packages/packages/python3-decimal_3.4.3-2_ar71xx.ipk. Installing python3-distutils (3.4.3-2) to root... Downloading http://downloads.openwrt.org/chaos_calmer/15.05/ar71xx/generic/packages/packages/python3-distutils_3.4.3-2_ar71xx.ipk. Installing python3-email (3.4.3-2) to root... Downloading http://downloads.openwrt.org/chaos_calmer/15.05/ar71xx/generic/packages/packages/python3-email_3.4.3-2_ar71xx.ipk. Installing python3-gdbm (3.4.3-2) to root... Downloading http://downloads.openwrt.org/chaos_calmer/15.05/ar71xx/generic/packages/packages/python3-gdbm_3.4.3-2_ar71xx.ipk. Installing libgdbm (1.11-1) to root... Downloading http://downloads.openwrt.org/chaos_calmer/15.05/ar71xx/generic/packages/packages/libgdbm_1.11-1_ar71xx.ipk. Installing python3-logging (3.4.3-2) to root... Downloading http://downloads.openwrt.org/chaos_calmer/15.05/ar71xx/generic/packages/packages/python3-logging_3.4.3-2_ar71xx.ipk. Installing python3-lzma (3.4.3-2) to root... Downloading http://downloads.openwrt.org/chaos_calmer/15.05/ar71xx/generic/packages/packages/python3-lzma_3.4.3-2_ar71xx.ipk. Installing liblzma (5.2.1-2) to root... Downloading http://downloads.openwrt.org/chaos_calmer/15.05/ar71xx/generic/packages/packages/liblzma_5.2.1-2_ar71xx.ipk. Installing python3-multiprocessing (3.4.3-2) to root... Downloading http://downloads.openwrt.org/chaos_calmer/15.05/ar71xx/generic/packages/packages/python3-multiprocessing_3.4.3-2_ar71xx.ipk. Installing python3-ncurses (3.4.3-2) to root... Downloading http://downloads.openwrt.org/chaos_calmer/15.05/ar71xx/generic/packages/packages/python3-ncurses_3.4.3-2_ar71xx.ipk. Installing python3-openssl (3.4.3-2) to root... Downloading http://downloads.openwrt.org/chaos_calmer/15.05/ar71xx/generic/packages/packages/python3-openssl_3.4.3-2_ar71xx.ipk. Installing python3-pydoc (3.4.3-2) to root... Downloading http://downloads.openwrt.org/chaos_calmer/15.05/ar71xx/generic/packages/packages/python3-pydoc_3.4.3-2_ar71xx.ipk. Installing python3-sqlite3 (3.4.3-2) to root... Downloading http://downloads.openwrt.org/chaos_calmer/15.05/ar71xx/generic/packages/packages/python3-sqlite3_3.4.3-2_ar71xx.ipk. Installing libsqlite3 (3081101-1) to root... Downloading http://downloads.openwrt.org/chaos_calmer/15.05/ar71xx/generic/packages/packages/libsqlite3_3081101-1_ar71xx.ipk. Installing python3-unittest (3.4.3-2) to root... Downloading http://downloads.openwrt.org/chaos_calmer/15.05/ar71xx/generic/packages/packages/python3-unittest_3.4.3-2_ar71xx.ipk. Installing python3-xml (3.4.3-2) to root... Downloading http://downloads.openwrt.org/chaos_calmer/15.05/ar71xx/generic/packages/packages/python3-xml_3.4.3-2_ar71xx.ipk. Configuring python3-base. Configuring libffi. Configuring libbz2. Configuring python3-light. Configuring python3-pydoc. Configuring liblzma. Configuring python3-email. Configuring python3-decimal. Configuring python3-xml. Configuring libxml2. Configuring python3-ncurses. Configuring python3-distutils. Configuring python3-codecs. Configuring python3-multiprocessing. Configuring python3-asyncio. Configuring python3-ctypes. Configuring libdb47. Configuring python3-dbm. Configuring libgdbm. Configuring python3-gdbm. Configuring python3-logging. Configuring python3-lzma. Configuring python3-openssl. Configuring libsqlite3. Configuring python3-sqlite3. Configuring python3-unittest. Configuring python3.