add a function to create a file

url2markdown/file.py

@@ -0,0 +1,8 @@
+import markdownify
+
+
+def write_to_file(article, header):
+    markdown = markdownify.markdownify(article.html)
+    with open(str(article.title) + ".md", 'a') as f:
+        f.write(header)
+        f.write(markdown)