Use `python3` explicitly to reduce conflict

all_tests.sh

@@ -1,3 +1,3 @@
 #!/bin/sh
 
-python -m unittest discover -p "*_test.py"
+python3 -m unittest discover -p "*_test.py"

myth

@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 """mythril.py: Bug hunting on the Ethereum blockchain
 
    http://www.github.com/b-mueller/mythril

tests/cmline_test.py

@@ -10,10 +10,10 @@ class CommandLineToolTestCase(unittest.TestCase):
         script_path = os.path.dirname(os.path.realpath(__file__))
         myth = os.path.join(script_path, '..', 'myth')
 
-        out = check_output([myth,'-d','-c', '0x5050']).decode("UTF-8")
+        out = check_output(['python3', myth,'-d','-c', '0x5050']).decode("UTF-8")
 
         self.assertEqual('0 POP\n1 POP\n', out)
 
-        out = check_output([myth,'-d', os.path.join(script_path,'testdata','metacoin.sol')]).decode("UTF-8")
+        out = check_output(['python3', myth,'-d', os.path.join(script_path,'testdata','metacoin.sol')]).decode("UTF-8")
 
         self.assertIn('0 PUSH1 0x60\n2 PUSH1 0x40', out)