diff --git a/test cases/common/105 find program path/program.py b/test cases/common/105 find program path/program.py
index b91071862..2ebc56419 100644
--- a/test cases/common/105 find program path/program.py	
+++ b/test cases/common/105 find program path/program.py	
@@ -1,3 +1,3 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 
 print("Found")
diff --git a/test cases/common/107 postconf/postconf.py b/test cases/common/107 postconf/postconf.py
index 9a23cfaf2..950c7064a 100644
--- a/test cases/common/107 postconf/postconf.py	
+++ b/test cases/common/107 postconf/postconf.py	
@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 
 import os
 
diff --git a/test cases/common/108 postconf with args/postconf.py b/test cases/common/108 postconf with args/postconf.py
index 3ed0450cc..cef7f790f 100644
--- a/test cases/common/108 postconf with args/postconf.py	
+++ b/test cases/common/108 postconf with args/postconf.py	
@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 
 import sys, os
 
diff --git a/test cases/common/113 generatorcustom/catter.py b/test cases/common/113 generatorcustom/catter.py
index a79b7395a..198fa98e2 100755
--- a/test cases/common/113 generatorcustom/catter.py	
+++ b/test cases/common/113 generatorcustom/catter.py	
@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 
 import sys
 
diff --git a/test cases/common/113 generatorcustom/gen.py b/test cases/common/113 generatorcustom/gen.py
index f9efb477d..c1e34ed6c 100755
--- a/test cases/common/113 generatorcustom/gen.py	
+++ b/test cases/common/113 generatorcustom/gen.py	
@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 
 import sys
 
diff --git a/test cases/common/118 allgenerate/converter.py b/test cases/common/118 allgenerate/converter.py
index cc2c5749b..f8e2ca05a 100755
--- a/test cases/common/118 allgenerate/converter.py	
+++ b/test cases/common/118 allgenerate/converter.py	
@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 
 import sys
 
diff --git a/test cases/common/129 object only target/obj_generator.py b/test cases/common/129 object only target/obj_generator.py
index f0239b44e..a33872aac 100755
--- a/test cases/common/129 object only target/obj_generator.py	
+++ b/test cases/common/129 object only target/obj_generator.py	
@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 
 # Mimic a binary that generates an object file (e.g. windres).
 
diff --git a/test cases/common/131 custom target directory install/docgen.py b/test cases/common/131 custom target directory install/docgen.py
index 4d80124de..245f37035 100644
--- a/test cases/common/131 custom target directory install/docgen.py	
+++ b/test cases/common/131 custom target directory install/docgen.py	
@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 
 import os
 import sys
diff --git a/test cases/common/133 configure file in generator/src/gen.py b/test cases/common/133 configure file in generator/src/gen.py
index 5bccece12..99b7cddb9 100755
--- a/test cases/common/133 configure file in generator/src/gen.py	
+++ b/test cases/common/133 configure file in generator/src/gen.py	
@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 
 import sys
 
diff --git a/test cases/common/134 generated llvm ir/copyfile.py b/test cases/common/134 generated llvm ir/copyfile.py
index da503e27c..ff42ac359 100644
--- a/test cases/common/134 generated llvm ir/copyfile.py	
+++ b/test cases/common/134 generated llvm ir/copyfile.py	
@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 
 import sys
 import shutil
diff --git a/test cases/common/135 generated assembly/copyfile.py b/test cases/common/135 generated assembly/copyfile.py
index da503e27c..ff42ac359 100644
--- a/test cases/common/135 generated assembly/copyfile.py	
+++ b/test cases/common/135 generated assembly/copyfile.py	
@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 
 import sys
 import shutil
diff --git a/test cases/common/48 test args/tester.py b/test cases/common/48 test args/tester.py
index c3c1edce7..0b4010ab9 100755
--- a/test cases/common/48 test args/tester.py	
+++ b/test cases/common/48 test args/tester.py	
@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 
 import sys
 
diff --git a/test cases/common/58 run target/check_exists.py b/test cases/common/58 run target/check_exists.py
index 62cbe2398..b6fc967eb 100755
--- a/test cases/common/58 run target/check_exists.py	
+++ b/test cases/common/58 run target/check_exists.py	
@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 
 import os
 import sys
diff --git a/test cases/common/58 run target/converter.py b/test cases/common/58 run target/converter.py
index 9f47ba552..8dd31fe2f 100644
--- a/test cases/common/58 run target/converter.py	
+++ b/test cases/common/58 run target/converter.py	
@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 
 import sys
 
diff --git a/test cases/common/58 run target/fakeburner.py b/test cases/common/58 run target/fakeburner.py
index 7f505d6bd..da3d0ac1e 100755
--- a/test cases/common/58 run target/fakeburner.py	
+++ b/test cases/common/58 run target/fakeburner.py	
@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 
 from __future__ import print_function
 
diff --git a/test cases/common/58 run target/meson.build b/test cases/common/58 run target/meson.build
index 8a06490b5..a1c5ad8ab 100644
--- a/test cases/common/58 run target/meson.build	
+++ b/test cases/common/58 run target/meson.build	
@@ -19,15 +19,17 @@ hex = custom_target('exe.hex',
   ],
 )
 
+fakeburner = find_program('fakeburner.py')
+
 # These emulates the Arduino flasher application. It sandwiches the filename inside
 # a packed argument. Thus we need to declare it manually.
 run_target('upload',
-  command : ['fakeburner.py', 'x:@0@:y'.format(exe.full_path())],
+  command : [fakeburner, 'x:@0@:y'.format(exe.full_path())],
   depends : exe,
 )
 
 run_target('upload2',
-  command : ['fakeburner.py', 'x:@0@:y'.format(hex.full_path())],
+  command : [fakeburner, 'x:@0@:y'.format(hex.full_path())],
   depends : hex,
 )
 
diff --git a/test cases/common/60 install script/myinstall.py b/test cases/common/60 install script/myinstall.py
index 969aba58e..812561e0e 100644
--- a/test cases/common/60 install script/myinstall.py	
+++ b/test cases/common/60 install script/myinstall.py	
@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 
 import os
 import sys
diff --git a/test cases/common/60 install script/src/myinstall.py b/test cases/common/60 install script/src/myinstall.py
index d8a5714ac..3b7ce37d4 100644
--- a/test cases/common/60 install script/src/myinstall.py	
+++ b/test cases/common/60 install script/src/myinstall.py	
@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 
 import os
 import sys
diff --git a/test cases/common/61 custom target source output/generator.py b/test cases/common/61 custom target source output/generator.py
index 42532ca5d..3464b0a85 100755
--- a/test cases/common/61 custom target source output/generator.py	
+++ b/test cases/common/61 custom target source output/generator.py	
@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 
 import sys, os
 
diff --git a/test cases/common/64 custom header generator/makeheader.py b/test cases/common/64 custom header generator/makeheader.py
index 0c5a228bf..f15683447 100644
--- a/test cases/common/64 custom header generator/makeheader.py	
+++ b/test cases/common/64 custom header generator/makeheader.py	
@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 
 # NOTE: this file does not have the executable bit set. This tests that
 # Meson can automatically parse shebang lines.
diff --git a/test cases/common/65 multiple generators/mygen.py b/test cases/common/65 multiple generators/mygen.py
index 020a38906..99dc33136 100755
--- a/test cases/common/65 multiple generators/mygen.py	
+++ b/test cases/common/65 multiple generators/mygen.py	
@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 
 import sys, os
 
diff --git a/test cases/common/72 build always/version_gen.py b/test cases/common/72 build always/version_gen.py
index 3973e6128..d7b01ca1a 100755
--- a/test cases/common/72 build always/version_gen.py	
+++ b/test cases/common/72 build always/version_gen.py	
@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 
 import sys, os, subprocess
 
diff --git a/test cases/common/76 configure file in custom target/src/mycompiler.py b/test cases/common/76 configure file in custom target/src/mycompiler.py
index e1750f8d9..b00c862db 100644
--- a/test cases/common/76 configure file in custom target/src/mycompiler.py	
+++ b/test cases/common/76 configure file in custom target/src/mycompiler.py	
@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 
 import sys
 
diff --git a/test cases/common/77 external test program/mytest.py b/test cases/common/77 external test program/mytest.py
index 7cdaf09a2..9947773f7 100755
--- a/test cases/common/77 external test program/mytest.py	
+++ b/test cases/common/77 external test program/mytest.py	
@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 
 from __future__ import print_function
 
diff --git a/test cases/common/78 ctarget dependency/gen1.py b/test cases/common/78 ctarget dependency/gen1.py
index f920e538e..0fa6ea1eb 100755
--- a/test cases/common/78 ctarget dependency/gen1.py	
+++ b/test cases/common/78 ctarget dependency/gen1.py	
@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 
 import time, sys
 
diff --git a/test cases/common/78 ctarget dependency/gen2.py b/test cases/common/78 ctarget dependency/gen2.py
index fc60e1eb2..b087b02cc 100755
--- a/test cases/common/78 ctarget dependency/gen2.py	
+++ b/test cases/common/78 ctarget dependency/gen2.py	
@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 
 import sys, os
 from glob import glob
diff --git a/test cases/common/93 private include/stlib/compiler.py b/test cases/common/93 private include/stlib/compiler.py
index 0555c1675..98dbe46fa 100755
--- a/test cases/common/93 private include/stlib/compiler.py	
+++ b/test cases/common/93 private include/stlib/compiler.py	
@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 
 import sys, os
 
diff --git a/test cases/common/95 dep fallback/gensrc.py b/test cases/common/95 dep fallback/gensrc.py
index da503e27c..ff42ac359 100644
--- a/test cases/common/95 dep fallback/gensrc.py	
+++ b/test cases/common/95 dep fallback/gensrc.py	
@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 
 import sys
 import shutil
diff --git a/test cases/common/95 dep fallback/subprojects/boblib/genbob.py b/test cases/common/95 dep fallback/subprojects/boblib/genbob.py
index 7da323382..34af7790e 100644
--- a/test cases/common/95 dep fallback/subprojects/boblib/genbob.py	
+++ b/test cases/common/95 dep fallback/subprojects/boblib/genbob.py	
@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 
 import sys
 
diff --git a/test cases/common/98 gen extra/srcgen.py b/test cases/common/98 gen extra/srcgen.py
index 86fd698f8..8988cd92f 100755
--- a/test cases/common/98 gen extra/srcgen.py	
+++ b/test cases/common/98 gen extra/srcgen.py	
@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 
 import sys
 import argparse
diff --git a/test cases/frameworks/7 gnome/resources-data/meson.build b/test cases/frameworks/7 gnome/resources-data/meson.build
index fd8cb0a2a..9458c2d90 100644
--- a/test cases/frameworks/7 gnome/resources-data/meson.build	
+++ b/test cases/frameworks/7 gnome/resources-data/meson.build	
@@ -1,5 +1,7 @@
 subdir('subdir')
 
+python3 = import('python3').find_python()
+
 fake_generator_script = '''
 import os, sys
 assert os.path.exists(sys.argv[1]), "File %s not found" % sys.argv[1]
@@ -11,6 +13,6 @@ print("This is a generated resource.")
 res3_txt = custom_target('res3.txt',
   input: 'res3.txt.in',
   output: 'res3.txt',
-  command: ['python3', '-c', fake_generator_script, '@INPUT@'],
+  command: [python3, '-c', fake_generator_script, '@INPUT@'],
   capture: true,
 )