replace formula sqlite install

builds/runtimes/python3

@@ -16,16 +16,19 @@ python_version=${BASE^} # this gives us only the filename with version number
 version_number=$(echo "$python_version" | cut -d- -f2) # this returns just X.X.X
 dep_url=https://python.org/ftp/python/${version_number}/${python_version}.tgz
 
-# shellcheck source=bin/utils
-source "$BIN_DIR/steps/sqlite3"
-
-sqlite3_version
-echo "Setting up SQLite3 Headers for $SQLITE3_VERSION"
-sqlite3_install "$OUT_PREFIX" "$SQLITE3_VERSION" 1
-
-echo "Building Python 3..."
-echo "Pulling from source: ${dep_url}"
+# Install SQLITE, as headers are not available out of the box on the stack
+apt-get install libsqlite3-dev
+needed=( libsqlite3-dev )
+if [[ $STACK != "heroku-16" && $STACK != "heroku-16" ]]; then
+	needed+=( realpath )
 
+# Check whether our packages are missing on the stack
+missing=$(comm -1 -3 <(dpkg-query -W -f '${package}\n' | sort) <(IFS=$'\n'; echo "${needed[*]}" | sort))
+if [[ "$missing" ]]; then
+    # install missing and needed packages
+	apt-get update -qq || { echo "Failed to 'apt-get update'. You must build this formula using Docker."; exit 1; }
+	apt-get install -q -y $missing
+fi
 
 curl -L "${dep_url}" | tar xz -C "${OUT_PREFIX}"
 mv "${OUT_PREFIX}/${python_version}" src