diff --git a/mypy/stubgen.py b/mypy/stubgen.py
index f2d31b7b94ee..81dc583be2c1 100644
--- a/mypy/stubgen.py
+++ b/mypy/stubgen.py
@@ -28,6 +28,7 @@
 
 import glob
 import imp
+import importlib
 import os.path
 import sys
 
@@ -50,10 +51,9 @@ def generate_stub(path, output_dir, _all_=None, target=None, add_header=False, m
     ast.accept(gen)
     if not target:
         target = os.path.join(output_dir, os.path.basename(path))
-    for i in range(target.count('/')):
-        subdir = os.path.dirname(target)
-        if subdir and not os.path.isdir(subdir):
-            os.makedirs(subdir)
+    subdir = os.path.dirname(target)
+    if subdir and not os.path.isdir(subdir):
+        os.makedirs(subdir)
     with open(target, 'w') as file:
         if add_header:
             write_header(file, module)
@@ -62,13 +62,10 @@ def generate_stub(path, output_dir, _all_=None, target=None, add_header=False, m
 
 def generate_stub_for_module(module, output_dir, quiet=False, add_header=False, sigs={},
                              class_sigs={}):
-    mod = __import__(module)
+    mod = importlib.import_module(module)
     imp.reload(mod)
-    components = module.split('.')
-    for attr in components[1:]:
-        mod = getattr(mod, attr)
     if is_c_module(mod):
-        target = '/'.join(components[:-1] + [components[-1] + '.pyi'])
+        target = module.replace('.', '/') + '.pyi'
         target = os.path.join(output_dir, target)
         generate_stub_for_c_module(module_name=module,
                                    target=target,
@@ -76,12 +73,11 @@ def generate_stub_for_module(module, output_dir, quiet=False, add_header=False,
                                    sigs=sigs,
                                    class_sigs=class_sigs)
     else:
-        target = '/'.join(module.split('.')[:-1])
-        modfnam = os.path.basename(mod.__file__)
-        if modfnam == '__init__.py':
-            target = os.path.join(target, module.split('.')[-1], '__init__.pyi')
+        target = module.replace('.', '/')
+        if os.path.basename(mod.__file__) == '__init__.py':
+            target += '/__init__.pyi'
         else:
-            target = os.path.join(target, modfnam.replace('.py', '.pyi'))
+            target += '.pyi'
         target = os.path.join(output_dir, target)
         generate_stub(mod.__file__, output_dir, getattr(mod, '__all__', None),
                       target=target, add_header=add_header, module=module)
diff --git a/mypy/stubgenc.py b/mypy/stubgenc.py
index 0fdcfa51948e..27b1bd58e6f4 100644
--- a/mypy/stubgenc.py
+++ b/mypy/stubgenc.py
@@ -3,6 +3,7 @@
 The public interface is via the mypy.stubgen module.
 """
 
+import importlib
 import os.path
 import re
 
@@ -14,8 +15,11 @@
 
 
 def generate_stub_for_c_module(module_name, target, add_header=True, sigs={}, class_sigs={}):
-    module = __import__(module_name)
+    module = importlib.import_module(module_name)
     assert is_c_module(module), '%s is not a C module' % module_name
+    subdir = os.path.dirname(target)
+    if subdir and not os.path.isdir(subdir):
+        os.makedirs(subdir)
     functions = []
     done = set()
     items = sorted(module.__dict__.items(), key=lambda x: x[0])
@@ -105,7 +109,10 @@ def generate_c_function_stub(module, name, obj, output, self_var=None, sigs={},
             else:
                 sig = sigs.get(name, '(*args, **kwargs)')
     sig = sig[1:-1]
-    if not sig:
+    if sig:
+        if sig.split(',', 1)[0] == self_var:
+            self_arg = ''
+    else:
         self_arg = self_arg.replace(', ', '')
     output.append('def %s(%s%s): pass' % (name, self_arg, sig))
 
@@ -125,6 +132,11 @@ def generate_c_type_stub(module, class_name, obj, output, sigs={}, class_sigs={}
                     self_var = 'self'
                 if attr == '__new__':
                     # TODO: We should support __new__.
+                    if '__init__' in obj.__dict__:
+                        # Avoid duplicate functions if both are present.
+                        # But is there any case where .__new__() has a
+                        # better signature than __init__() ?
+                        continue
                     attr = '__init__'
                 generate_c_function_stub(module, attr, value, methods, self_var, sigs=sigs,
                                          class_name=class_name, class_sigs=class_sigs)