Reads the exciting input from a string

def from_string(data):
        """
        Reads the exciting input from a string
        """
       
        root=ET.fromstring(data)
        speciesnode=root.find('structure').iter('species')
        elements = []
        positions = []
        vectors=[]
        lockxyz=[]
        # get title
        title_in=str(root.find('title').text)
        # Read elements and coordinates
        for nodes in speciesnode:
            symbol = nodes.get('speciesfile').split('.')[0]
            if len(symbol.split('_'))==2:
              symbol=symbol.split('_')[0]
            if Element.is_valid_symbol(symbol):
                # Try to recognize the element symbol
                element = symbol
            else:
                raise NLValueError("Unknown element!")
            natoms = nodes.getiterator('atom')
            for atom in natoms:
                x, y, z = atom.get('coord').split()
                positions.append([float(x), float(y), float(z)])
                elements.append(element)
                # Obtain lockxyz for each atom
                if atom.get('lockxyz') is not None:
                    lxy=[]
                    for l in atom.get('lockxyz').split():
                        if l=='True' or l=='true':
                            lxyz.append(True)
                        else:
                            lxyz.append(False)
                    lockxyz.append(lxyz)
                else:
                    lockxyz.append([False, False, False])
        #check the atomic positions type
        if 'cartesian' in root.find('structure').attrib.keys():
          if root.find('structure').attrib['cartesian']:
            cartesian=True
            for i in range(len(positions)):
                for j in range(3):
                    positions[i][j]=positions[i][j]*ExcitingInput.bohr2ang
            print(positions)
        else:
          cartesian=False
        # get the scale attribute
        scale_in=root.find('structure').find('crystal').get('scale')
        if scale_in:
            scale=float(scale_in)*ExcitingInput.bohr2ang
        else:
            scale=ExcitingInput.bohr2ang
       # get the stretch attribute
        stretch_in=root.find('structure').find('crystal').get('stretch')
        if stretch_in:
          stretch=np.array([float(a) for a in stretch_in])
        else:
          stretch=np.array([1.0,1.0,1.0])
        # get basis vectors and scale them accordingly
        basisnode=root.find('structure').find('crystal').iter('basevect')
        for vect in basisnode:
          x, y, z=vect.text.split()
          vectors.append([float(x)*stretch[0]*scale,
                          float(y)*stretch[1]*scale,
                          float(z)*stretch[2]*scale])
        # create lattice and structure object
        lattice_in=Lattice(vectors)
        structure_in=Structure(lattice_in,elements,positions,coords_are_cartesian=cartesian)

        return ExcitingInput(structure_in, title_in, lockxyz)