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To exame a string is a real number or float number or not (AAA): code:          
         
Output:         
         

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Check if all the characters in the text are digits: need to convert it to a string before checking (AAA: this is the best way to check if the string is an integer or not. If it is an integer, then use int(x) to ensure the variable is in integer type): code:          
         
Output:         
         

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Remove dot to check if it not a string (to ensure it is a float or integer):: Need to convert the item to string first (AAA: this is the best way to check if the "string" is not a real string but it is a foat or interger.): code:          
         
Output (the last one needs to be converted to a string before "replace"):         
         

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Check if all the characters in the text are digits: code:          
         
Output:         
         

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Get the length of a string (number of characters): code:          
         
Output:         
         

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Get the length of a string (number of characters) with a special character in it: code:          
         
Output:         
         

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