I have the following dataset:

and I would like to get the first word for every string inside lista_asm, so I would like to get: jmp,push,uncomisd,...etc

what I am doing to do this is the following:

dataFrame['opcodes'] = dataFrame['lista_asm'].apply(lambda x:[i.split()[0] for i in x])

but it gives me back the following error message:

   3589             else:
   3590                 values = self.astype(object).values
-> 3591                 mapped = lib.map_infer(values, f, convert=convert_dtype)
   3592 
   3593         if len(mapped) and isinstance(mapped[0], Series):

pandas/_libs/lib.pyx in pandas._libs.lib.map_infer()

<ipython-input-18-5506b5721bf1> in <lambda>(x)
----> 1 dataFrame['opcodes'] = dataFrame['lista_asm'].apply(lambda x:[i.split()[0].strip() for i in x])

IndexError: list index out of range

I don't understand what is wrong. Can somebody please help me?