moved dependency checking to utility module

utility.py

@@ -1,7 +1,7 @@
 from functools import wraps
 from tempfile import mkdtemp
 from shutil import rmtree
-from subprocess import check_output
+from subprocess import check_output, CalledProcessError
 
 
 VERBOSE = True
@@ -55,4 +55,16 @@ class temporary_directory:
 
 
 def get_output(*args, **kwargs):
-    return check_output(*args, **kwargs).decode().rstrip('\n')
+    return check_output(*args, **kwargs).decode().rstrip('\n')
+
+
+@call_verbose(before_message='Checking your system for dependencies... ', after_message='Found all!')
+def check_dependencies(check_for):
+    error_str = '\nMissing dependencies: {}'
+    missing = []
+
+    for command in check_for:
+        try: check_output(command)
+        except (CalledProcessError, FileNotFoundError): missing.append(command[0])
+
+    if missing: exit(error_str.format(', '.join(missing)))