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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:

def _read_isotopedatabase(self, ffname='isotopedatabase.txt'):
        '''
        This private method reads the isotopedatabase.txt file in sldir
        run dictory and returns z, a, elements, the cutoff mass for each
        species that delineate beta+ and beta- decay and the logical in
        the last column. Also provides charge_from_element dictionary
        according to isotopedatabase.txt.

        '''
        name=self.sldir+ffname
        z_db, a_db, el_db, stable_a_db,logic_db=\
            np.loadtxt(name,unpack=True,dtype='str')
        z_db=np.array(z_db,dtype='int')
        a_db=np.array(a_db,dtype='int')
        stable_a_db=np.array(stable_a_db,dtype='int')

        # charge number for element name from dictionary in isotopedatabase.txt
        charge_from_element_name={}
        for name in self.stable_names:
            if name=='Neutron' or name=='Neut' or name=='NEUT' or name=='N-1':
                name='nn'
            try:
                zz=z_db[np.where(el_db==name)][0]
                charge_from_element_name[name]=zz
            except IndexError:
                print(name+" does not exist in this run")
        return z_db, a_db, el_db, stable_a_db,logic_db,charge_from_element_name