Simplify brackets_check(): reimplement without the generator.

stix2patterns/helpers.py

@@ -11,13 +11,12 @@ def brackets_check(pattern):
  :return: True if the pattern had its brackets; False if not
  """
  if isinstance(pattern, six.string_types):
- # the non-whitespace chars
- non_ws_chars = (c for c in pattern if not c.isspace())
 
- # There can be an arbitrary number of open parens first... skip over those
- c = next(non_ws_chars, None)
- while c == "(":
- c = next(non_ws_chars, None)
+ # There can be an arbitrary number of open parens first... skip over
+ # those
+ for c in pattern:
+ if c != "(" and not c.isspace():
+ break
 
  if c == "[":
  result = True