<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def signature(self, name, file_name, file_type, file_text, **kwargs):
 """Add Signature data to Batch object. Valid file_types: + Snort ® + Suricata + YARA + ClamAV ® + OpenIOC + CybOX ™ + Bro + Regex + SPL - Splunk ® Search Processing Language Args: name (str):
 The name for this Group. file_name (str):
 The name for the attached signature for this Group. file_type (str):
 The signature type for this Group. file_text (str):
 The signature content for this Group. date_added (str, kwargs):
 The date timestamp the Indicator was created. xid (str, kwargs):
 The external id for this Group. Returns: obj: An instance of Signature. """

        group_obj = Signature(name, file_name, file_type, file_text, **kwargs)
        return self._group(group_obj)