<s>[INST] Create a calculator in the Python programming language [/INST] Okay here we go, first, let's define a class and its constructor. Also let's add a few simple member functions.
```python
class calculator:
    def __init__(self): pass
    def add(self, a, b): return a+b
    def multiplicate(self, a, b): return a*b
    def exponential(self, a, b): return a**b
    def sqrt(self, a): return a**0.5
```</s>\ <s>[INST] Can we update this program to work on text input like 2+10/5 or 3*9-7? Parenthesis support is not required. Just addition, subtraction, multiplication and division is enough. [/INST] Yes, we can update the program to handle text input. We can use the eval() function in Python to evaluate the expression string and return the result. Here's the updated code:

class Calculator:
    def __init__(self):
        pass

    def calculate(self, expression):
        try:
            result = eval(expression)
            return result
        except:
            return "Invalid expression"

Now, you can create an instance of the Calculator class and use the calculate() method to evaluate an expression:

calc = Calculator()
result = calc.calculate("2 + 10 / 5")  # result will be 4.0
result = calc.calculate("3 * 9 - 7")  # result will be 20

Note that eval() function can evaluate any Python expression. Therefore, it is important to make sure that the input is sanitized and comes from a trusted source. In this example, we have not added any input validation or sanitation, so it is vulnerable to code injection attacks.</s>