Are you trying to use the variable "c", but you forgot something to assign
nigel_Jast87 answered on April 4th 20 at 00:49
Name is not defined could mean:
1. You haven't created the variable "c"
2. You have created a variable "c" and it was deleted Garbage Collector
3. You have created a variable "c" out-of-scope of this part of the code
4. You are sealed and have created another variable (for example, "s" Latin)