Fix deprecation warnings in 3.7

bonobo/config/processors.py

@@ -1,4 +1,4 @@
-from collections import Iterable
+from collections.abc import Iterable
 from contextlib import contextmanager
 from functools import partial
 from inspect import signature

bonobo/util/environ.py

@@ -6,7 +6,7 @@ import warnings
 from contextlib import contextmanager
 
 __escape_decoder = codecs.getdecoder("unicode_escape")
-__posix_variable = re.compile("\$\{[^\}]*\}")
+__posix_variable = re.compile(r"\$\{[^\}]*\}")
 
 
 def parse_var(var):

bonobo/util/errors.py

@@ -24,7 +24,7 @@ def sweeten_errors():
             length = len(pre_re.sub("\\1\\2\\3", arg))
 
             arg = pre_re.sub(w("\\1") + term.bold("\\2") + w("\\3"), arg)
-            arg = re.sub("^  \$ (.*)", term.lightblack("  $ ") + term.reset("\\1"), arg)
+            arg = re.sub(r"^  \$ (.*)", term.lightblack("  $ ") + term.reset("\\1"), arg)
 
             return (arg, length)