How to get symbol in IDA like done in BN code

Question

I am converting BN code into IDA Pro and stuck at this point, following are lines in the code which gives the symbol call

#####Get call symbol (if it exists)
dr.get_symbol(inst.tokens)

and

####### NOTE: Might contain FPs. E.g., "call [ebx + 0x4]"
#####Extract call symbol if it exists
def get_symbol(self, token):
    token = [str(t) for t in token]
    if '[' not in token:
         return

start = token.index('[')
end = token.index(']')
symbol = ' '.join(token[start+1:end])
self.api.append(symbol)

I want to convert the above code and want the following output in TXT file, but I am getting only strings and not in the register format like below.

Sample output:

---------------** 

 ++++++ API Features ++++++
    APIs: ebp + 0x8  { arg2 };eax;ecx;ecx + esi;ebp - 0x18  { var_1c }
 
++++++ API Features ++++++
    APIs: ebp + 0x8  { arg1 };edi