Add condition function

install.py

@@ -207,6 +207,12 @@ class Installer:
         ui.info()
 
 
+def evaluate_condition(command: str) -> bool:
+    """Run a bash command. On success return True, else return False."""
+
+    return subprocess.run(command, shell=True).returncode == 0
+
+
 def main() -> None:
     """Parse args and instantiate the Installer."""