python regular expression - re.findall() in list
Question: This is my list:

    
    
    lista=[u'REG_S_3_UMTS_0_0 (RNC)', u'REG_S_3_UMTS_0_1 (RNC)', u'REG_S_3_UMTS_0_2 (RNC)', u'REG_S_2_GSM_NORT_CBSP_bsc_0_0 (BSC)', u'REG_S_2_GSM_NORT_CBSP_bsc_0_1 (BSC)', u'REG_S_2_GSM_NORT_CBSP_bsc_0_2 (BSC)', u'REG_S_3_GSM_ERIC_CBSP_bsc_0_0 (BSC)', u'REG_S_3_GSM_ERIC_CBSP_bsc_0_1 (BSC)', u'REG_S_3_GSM_ERIC_CBSP_bsc_0_2 (BSC)', u'REG_S_3_GSM_HUAP_CBSM_bsc_0_0 (BSC)', u'REG_S_3_GSM_HUAP_CBSM_bsc_0_1 (BSC)', u'REG_S_3_GSM_HUAP_CBSM_bsc_0_2 (BSC)', u'REG_S_3_GSM_HUA_CBSM_bsc_0_0 (BSC)', u'REG_S_3_GSM_HUA_CBSM_bsc_0_1 (BSC)', u'REG_S_3_GSM_HUA_CBSM_bsc_0_2 (BSC)', u'REG_S_3_GSM_IPAC_SABP_bsc_0_0 (BSC)', u'REG_S_3_GSM_IPAC_SABP_bsc_0_1 (BSC)', u'REG_S_3_GSM_IPAC_SABP_bsc_0_2 (BSC)', u'REG_S_3_GSM_NOKI_CLNS_bsc_0_0 (BSC)', u'REG_S_3_GSM_NOKI_CLNS_bsc_0_1 (BSC)', u'REG_S_3_GSM_NOKI_CLNS_bsc_0_2 (BSC)', u'REG_S_3_GSM_NOKI_RFC1_bsc_0_0 (BSC)', u'REG_S_3_GSM_NOKI_RFC1_bsc_0_1 (BSC)', u'REG_S_3_GSM_NOKI_RFC1_bsc_0_2 (BSC)', u'REG_S_3_GSM_NORT_CBSP_bsc_0_0 (BSC)', u'REG_S_3_GSM_NORT_CBSP_bsc_0_1 (BSC)', u'REG_S_3_GSM_NORT_CBSP_bsc_0_2 (BSC)', u'REG_S_3_GSM_SIEM_BSCI_bsc_0_0 (BSC)', u'REG_S_3_GSM_SIEM_BSCI_bsc_0_1 (BSC)', u'REG_S_3_GSM_SIEM_BSCI_bsc_0_2 (BSC)', u'REG_S_GSM_ERIC_CBSP_bsc_0_0 (BSC)', u'REG_S_GSM_ERIC_CBSP_bsc_0_1 (BSC)', u'REG_S_GSM_ERIC_CBSP_bsc_0_2 (BSC)', u'REG_S_GSM_HUAP_CBSM_bsc_0_0 (BSC)', u'REG_S_GSM_HUAP_CBSM_bsc_0_1 (BSC)', u'REG_S_GSM_HUAP_CBSM_bsc_0_2 (BSC)', u'REG_S_GSM_HUA_CBSM_bsc_0_0 (BSC)', u'REG_S_GSM_HUA_CBSM_bsc_0_1 (BSC)', u'REG_S_GSM_HUA_CBSM_bsc_0_2 (BSC)', u'REG_S_GSM_NORT_CBSP_bsc_0_0 (BSC)', u'REG_S_GSM_NORT_CBSP_bsc_0_1 (BSC)', u'REG_S_GSM_NORT_CBSP_bsc_0_2 (BSC)', u'Pool ID: 200']
    

And that's my function:

    
    
    def Filter_List(lista):
    
         string = ''.join(lista)
         match = re.findall(r"\(([A-Z]+)\)|Pool ID", string)
         return match
    

As a result I get:

    
    
    [u'RNC', u'RNC', u'RNC', u'BSC', u'BSC', u'BSC', u'BSC', u'BSC', u'BSC', u'BSC', u'BSC', u'BSC', u'BSC', u'BSC', u'BSC', u'BSC', u'BSC', u'BSC', u'BSC', u'BSC', u'BSC', u'BSC', u'BSC', u'BSC', u'BSC', u'BSC', u'BSC', u'BSC', u'BSC', u'BSC', u'BSC', u'BSC', u'BSC', u'BSC', u'BSC', u'BSC', u'BSC', u'BSC', u'BSC', u'BSC', u'BSC', u'BSC', u'']
    

But the last element (it should be: Pool ID) doesn't display.There's only: u''
. Does anyone know how should I change my expression? Thanks in advance !!!


Answer: Note that
[**`re.findall`**](https://docs.python.org/2/library/re.html#re.findall)
returns (list of) tuples if a regex pattern has capture groups defined. Remove
it:

    
    
    import re
    lista=[u'REG_S_3_UMTS_0_0 (RNC)', u'REG_S_3_UMTS_0_1 (RNC)', u'REG_S_3_UMTS_0_2 (RNC)', u'REG_S_2_GSM_NORT_CBSP_bsc_0_0 (BSC)', u'REG_S_2_GSM_NORT_CBSP_bsc_0_1 (BSC)', u'REG_S_2_GSM_NORT_CBSP_bsc_0_2 (BSC)', u'REG_S_3_GSM_ERIC_CBSP_bsc_0_0 (BSC)', u'REG_S_3_GSM_ERIC_CBSP_bsc_0_1 (BSC)', u'REG_S_3_GSM_ERIC_CBSP_bsc_0_2 (BSC)', u'REG_S_3_GSM_HUAP_CBSM_bsc_0_0 (BSC)', u'REG_S_3_GSM_HUAP_CBSM_bsc_0_1 (BSC)', u'REG_S_3_GSM_HUAP_CBSM_bsc_0_2 (BSC)', u'REG_S_3_GSM_HUA_CBSM_bsc_0_0 (BSC)', u'REG_S_3_GSM_HUA_CBSM_bsc_0_1 (BSC)', u'REG_S_3_GSM_HUA_CBSM_bsc_0_2 (BSC)', u'REG_S_3_GSM_IPAC_SABP_bsc_0_0 (BSC)', u'REG_S_3_GSM_IPAC_SABP_bsc_0_1 (BSC)', u'REG_S_3_GSM_IPAC_SABP_bsc_0_2 (BSC)', u'REG_S_3_GSM_NOKI_CLNS_bsc_0_0 (BSC)', u'REG_S_3_GSM_NOKI_CLNS_bsc_0_1 (BSC)', u'REG_S_3_GSM_NOKI_CLNS_bsc_0_2 (BSC)', u'REG_S_3_GSM_NOKI_RFC1_bsc_0_0 (BSC)', u'REG_S_3_GSM_NOKI_RFC1_bsc_0_1 (BSC)', u'REG_S_3_GSM_NOKI_RFC1_bsc_0_2 (BSC)', u'REG_S_3_GSM_NORT_CBSP_bsc_0_0 (BSC)', u'REG_S_3_GSM_NORT_CBSP_bsc_0_1 (BSC)', u'REG_S_3_GSM_NORT_CBSP_bsc_0_2 (BSC)', u'REG_S_3_GSM_SIEM_BSCI_bsc_0_0 (BSC)', u'REG_S_3_GSM_SIEM_BSCI_bsc_0_1 (BSC)', u'REG_S_3_GSM_SIEM_BSCI_bsc_0_2 (BSC)', u'REG_S_GSM_ERIC_CBSP_bsc_0_0 (BSC)', u'REG_S_GSM_ERIC_CBSP_bsc_0_1 (BSC)', u'REG_S_GSM_ERIC_CBSP_bsc_0_2 (BSC)', u'REG_S_GSM_HUAP_CBSM_bsc_0_0 (BSC)', u'REG_S_GSM_HUAP_CBSM_bsc_0_1 (BSC)', u'REG_S_GSM_HUAP_CBSM_bsc_0_2 (BSC)', u'REG_S_GSM_HUA_CBSM_bsc_0_0 (BSC)', u'REG_S_GSM_HUA_CBSM_bsc_0_1 (BSC)', u'REG_S_GSM_HUA_CBSM_bsc_0_2 (BSC)', u'REG_S_GSM_NORT_CBSP_bsc_0_0 (BSC)', u'REG_S_GSM_NORT_CBSP_bsc_0_1 (BSC)', u'REG_S_GSM_NORT_CBSP_bsc_0_2 (BSC)', u'Pool ID: 200']
    string = ''.join(lista)
    match = re.findall(r"\([A-Z]+\)|Pool ID", string)
    print(match)
    

See [this Python demo](https://ideone.com/3lrsnj) returning

`[u'(RNC)', u'(RNC)', u'(RNC)', u'(BSC)', u'(BSC)', u'(BSC)', u'(BSC)',
u'(BSC)', u'(BSC)', u'(BSC)', u'(BSC)', u'(BSC)', u'(BSC)', u'(BSC)',
u'(BSC)', u'(BSC)', u'(BSC)', u'(BSC)', u'(BSC)', u'(BSC)', u'(BSC)',
u'(BSC)', u'(BSC)', u'(BSC)', u'(BSC)', u'(BSC)', u'(BSC)', u'(BSC)',
u'(BSC)', u'(BSC)', u'(BSC)', u'(BSC)', u'(BSC)', u'(BSC)', u'(BSC)',
u'(BSC)', u'(BSC)', u'(BSC)', u'(BSC)', u'(BSC)', u'(BSC)', u'(BSC)', u'Pool
ID']`

