Sepearate python and vimscript files.

Also added function which can utilize either +python or +python3
depending on what is available on vim.

ftplugin/python/pylint_fn.py

@@ -0,0 +1,71 @@
+"""
+Get pylint oputput on current buffer
+"""
+import sys
+import re
+from StringIO import StringIO
+
+try:
+    from pylint import lint
+    from pylint.reporters.text import TextReporter
+except ImportError:
+    raise AssertionError('Error: pylint_fm.vim requires module pylint')
+
+import vim
+
+
+class VImPylint(object):
+    """Vim pylint interface"""
+
+    sys_stderr = sys.stderr
+    dummy_stderr = StringIO()
+    conf_msg = 'No config file found, using default configuration\n'
+
+    @classmethod
+    def run(self):
+        """execute pylint and fill the quickfix"""
+
+        # clear QF window
+        vim.command('call setqflist([])')
+
+        # args
+        args = ['-rn',  # display only the messages instead of full report
+                vim.current.buffer.name]
+
+        buf = StringIO()  # file-like buffer, instead of stdout
+        reporter = TextReporter(buf)
+
+        sys.stderr = self.dummy_stderr
+        lint.Run(args, reporter=reporter, exit=False)
+        sys.stderr = self.sys_stderr
+
+        self.dummy_stderr.seek(0)
+        error_list = self.dummy_stderr.readlines()
+        self.dummy_stderr.truncate(0)
+        if error_list and self.conf_msg in error_list:
+            error_list.remove(self.conf_msg)
+            if error_list:
+                raise Exception(''.join(error_list))
+
+        buf.seek(0)
+
+        bufnr = vim.current.buffer.number
+        error_list = []
+
+        error_re = re.compile(r'^(?P<type>[C,R,W,E,F]):\s+?'
+                              r'(?P<lnum>[0-9]+),\s+?'
+                              r'(?P<col>[0-9]+):\s'
+                              r'(?P<text>.*)$')
+        for line in buf:
+            line = line.rstrip()  # remove trailing newline character
+
+            error_line = error_re.match(line)
+            if error_line:
+                error_line = error_line.groupdict()
+                error_line["bufnr"] = bufnr
+
+                error_list.append(error_line)
+
+        vim.command('call setqflist(%s)' % str(error_list))
+        if error_list:
+            vim.command('copen')