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'is' vs '==' in Python

 


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'is' vs '==' in Python

In Python, both is and == are used for comparisons, but they serve different purposes.

1. == (Equality Operator)

The == operator checks if the values of two objects are equal. It evaluates to True if the objects referred to have the same value.

Example:


# Using == to check equality
a = [1, 2, 3]
b = [1, 2, 3]
print(a == b)  # Output: True

2. is (Identity Operator)

The is operator checks if two variables point to the same object in memory. It evaluates to True if the objects referred to are the same.

Example:


# Using is to check identity
a = [1, 2, 3]
b = [1, 2, 3]
print(a is b)  # Output: False

c = a
print(a is c)  # Output: True

3. Key Differences

  • == checks for value equality. It returns True if the values of the two objects are the same.
  • is checks for reference equality. It returns True if both variables point to the same object (i.e., same memory location).

Understanding the difference between is and == is crucial when comparing objects in Python, especially when dealing with mutable types like lists and dictionaries.

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