caught blind case if engine fails to build when both not installed

pkg-install

@@ -48,14 +48,11 @@ ENTRYPOINT [\"/usr/bin/env\", \"{command}\"]"
 
 # check if either docker or podman are installed
 
-docker_check = which("docker")
-
-podman_check = which("podman")
-
-if docker_check is None:
+try:
+    if which("docker") is None:
         print("Docker not installed, building with Podman")
         engine = "podman"
-elif podman_check is None:
+    elif which("podman") is None:
         engine = "docker"
     else:
         print("Podman/Docker are not installed! Exiting...")
@@ -63,4 +60,6 @@ else:
 
 
     subprocess.run([engine, "build", "-t", command, "-"], input = dockerfile, encoding = 'UTF-8')
-
+except FileNotFoundError:
+    print("An Error has occured while attempting to build the image.")
+    exit(1)