Return True if the process[key] should be filtered according to the current filter

def _is_process_filtered(self, process, key=None):
        """Return True if the process[key] should be filtered according to the current filter"""
        if key is None:
            key = self.filter_key
        try:
            # If the item process[key] is a list, convert it to a string
            # in order to match it with the current regular expression
            if isinstance(process[key], list):
                value = ' '.join(process[key])
            else:
                value = process[key]
        except KeyError:
            # If the key did not exist
            return False
        try:
            return self._filter_re.match(value) is None
        except (AttributeError, TypeError):
            # AttributeError
            # Filter processes crashs with a bad regular expression pattern (issue #665)
            # TypeError
            # Filter processes crashs if value is None (issue #1105)
            return False