def get_regex_strings(self, regular_expressions):
str_list = []<EOL>if regular_expressions.count is None:<EOL><INDENT>return None<EOL><DEDENT>for i in self.get_strings():<EOL><INDENT>if re.match(regular_expressions, i):<EOL><INDENT>str_list.append(i)<EOL><DEDENT><DEDENT>return str_list<EOL>
Return all target strings matched the regex

:param regular_expressions: the python regex
:type regular_expressions: string

:rtype: a list of strings matching the regex expression