Update lif_cell.rst (#2347)

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doc/python/lif_cell.rst

@@ -13,9 +13,9 @@ LIF cells
     .. function:: lif_cell(source, target, **, tau_m, V_th, C_m, E_L, E_R, V_m, t_ref)
 
         Constructor: assigns the label ``source`` to the single built-in source
-        on the cell; and assigns the label ``target`` to the single built-in
+        on the cell, and assigns the label ``target`` to the single built-in
         target on the cell. Optional parameters may be given and set the
-        correspoding physical parameters of the cell
+        corresponding physical parameters of the cell
 
     .. attribute:: source