Update pvsystem.py

Author: RDaxini

pvlib/pvsystem.py

@@ -2234,7 +2234,7 @@ def sapm(effective_irradiance, temp_cell, module):
     of modules. The CEC module database does not contain these parameters.
     Both databases can be accessed using :py:func:`retrieve_sam`. The full list
     of SAPM parameters is presented in the table below. Those that are required
-    in ``module`` are: `Bvmpo`, `Mbvmp`, `Bvoco`, `Mbvoc`, `N`,
+    in ``module`` are: `Bvmpo`, `Mbvmp`, `Bvoco`, `Mbvoc`, `N`, and
     `Cells_in_Series`
 
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