add (overwrite with) mypy stubs, if available

stdlib/3/csv.pyi

@@ -0,0 +1,77 @@
+# Stubs for csv (Python 3.4)
+#
+# NOTE: This dynamically typed stub was automatically generated by stubgen.
+
+from typing import Any
+
+QUOTE_ALL = ...  # type: int
+QUOTE_MINIMAL = ...  # type: int
+QUOTE_NONE = ...  # type: int
+QUOTE_NONNUMERIC = ...  # type: int
+
+class Error(Exception): ...
+
+def writer(csvfile, dialect=..., **fmtparams): ...
+def reader(csvfile, dialect=..., **fmtparams): ...
+def register_dialect(name, dialect=..., **fmtparams): ...
+def unregister_dialect(name): ...
+def get_dialect(name): ...
+def list_dialects(): ...
+def field_size_limit(new_limit=...): ...
+
+class Dialect:
+    delimiter = ...  # type: Any
+    quotechar = ...  # type: Any
+    escapechar = ...  # type: Any
+    doublequote = ...  # type: Any
+    skipinitialspace = ...  # type: Any
+    lineterminator = ...  # type: Any
+    quoting = ...  # type: Any
+    def __init__(self): ...
+
+class excel(Dialect):
+    delimiter = ...  # type: Any
+    quotechar = ...  # type: Any
+    doublequote = ...  # type: Any
+    skipinitialspace = ...  # type: Any
+    lineterminator = ...  # type: Any
+    quoting = ...  # type: Any
+
+class excel_tab(excel):
+    delimiter = ...  # type: Any
+
+class unix_dialect(Dialect):
+    delimiter = ...  # type: Any
+    quotechar = ...  # type: Any
+    doublequote = ...  # type: Any
+    skipinitialspace = ...  # type: Any
+    lineterminator = ...  # type: Any
+    quoting = ...  # type: Any
+
+class DictReader:
+    restkey = ...  # type: Any
+    restval = ...  # type: Any
+    reader = ...  # type: Any
+    dialect = ...  # type: Any
+    line_num = ...  # type: Any
+    fieldnames = ...  # type: Any # Actually a property
+    def __init__(self, f, fieldnames=None, restkey=None, restval=None, dialect='',
+                 *args, **kwds): ...
+    def __iter__(self): ...
+    def __next__(self): ...
+
+class DictWriter:
+    fieldnames = ...  # type: Any
+    restval = ...  # type: Any
+    extrasaction = ...  # type: Any
+    writer = ...  # type: Any
+    def __init__(self, f, fieldnames, restval='', extrasaction='', dialect='', *args, **kwds): ...
+    def writeheader(self): ...
+    def writerow(self, rowdict): ...
+    def writerows(self, rowdicts): ...
+
+class Sniffer:
+    preferred = ...  # type: Any
+    def __init__(self): ...
+    def sniff(self, sample, delimiters=None): ...
+    def has_header(self, sample): ...