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is not            It yields True if the operands on either side  >>> type(b) is not int
                           of  the  operator  are  different  objects  or       False
                           different types, and False otherwise.  >>> type(c) is not list
                                                                      True
                                                                  >>> a is not b
                                                                      True
                                                                  >>> a = b
                                                                  >>> a is not b
                                                                      False

        7.5.6 Membership Operators

        These operators are used to check whether a particular value is a member of a given sequence and return either True
        or False.
                                               Table 7.6: Membership Operators

           Operator               Explanation                                    Examples
         in            The expression a in b yields True  >>> myList = [0, -4, 5, 8, 10, 50, 4]
                       if  the  object  a is included  in  b and   >>> 5 in myList
                       False otherwise.                       True
                                                          >>> 100 in myList
                                                              False
         not in        The expression a not in b yields  >>> myList = [0, -4, 5, 8, 10, 50, 4]
                       True if the object a is not included in   >>> 5 not in myList
                       b and False otherwise.                 False
                                                          >>> 100 not in myList
                                                              True

        7.6 Expressions

        An expression in Python is a valid combination of constants, variables, and operators. A single value of any type
        or the name of an object (i.e. a variable) are examples of the simplest expressions. On evaluation, an expression
        yields a value. The type of an expression is based on the types of operators and operands that are used in it. An
        expression yields a value, and the type of the value that an expression yields is called the type of the expression.
        Assuming that the variables a, b, and num have values 5, 7, and 12.5 respectively, some examples of valid
        expressions are:
             Expression                           Type

          (i)  50                                 int
          (ii)  a                                 int
         (iii)  a == 5 and b>0                    bool
         (iv)  num + 45.6 - 6                     float
          (v)  22/7*2*2                           float
         (vi)  "abc"*3                            str

        7.7 Precedence of Operators in Python

        When an expression involves multiple operators, Python resolves the order of execution according to the precedence
        of operators.  An operator with higher precedence will be evaluated before an operator with lower precedence. As
        a general rule, the unary operators have higher precedence over binary operators. Among the binary operators, the
        table gives the precedence from highest to lowest.


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