[web2py] index in list of fields

[simon]

Please can someone explain why, for a list of fields, that 
fields.index("anything at all") always evaluates to 0.

For example this  prints 23 and 0. 

t=db.todo
fields = [t.id, t.customer, t.subject, t.completed, t.modified_by]
if 23 in fields: print("23 is in there")
print(fields.index("hshshshs"))





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