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Keywords and Identifiers

Keywords and Identifiers

 

What are Keywords and Identifiers?

Keywords and identifiers are two types of names used in Python. Keywords are reserved words that have special meaning to the Python interpreter. Identifiers are names that you can use to refer to variables, functions, classes, etc.

Keywords

There are 33 keywords in Python. These keywords cannot be used as variable names, function names, or any other identifier. They are used to define the syntax and structure of the Python language.

Here is a list of all the keywords in Python:

Code snippet
and
as
assert
break
class
continue
def
del
elif
else
except
finally
for
from
global
if
import
in
is
lambda
nonlocal
not
or
pass
print
raise
return
while
with
yield

Identifiers

Identifiers are names that you can use to refer to variables, functions, classes, etc. They can be any combination of letters, numbers, and underscores. The first character of an identifier must be a letter or an underscore.

Here are some rules for naming identifiers:

  • Identifiers must start with a letter or an underscore.
  • Identifiers can contain letters, numbers, and underscores.
  • Identifiers cannot contain spaces.
  • Identifiers cannot be the same as keywords.
  • Identifiers should be descriptive.

Here are some examples of valid identifiers:

Code snippet
my_variable
my_function
my_class

Here are some examples of invalid identifiers:

Code snippet
1variable
my function
class

Using Keywords and Identifiers

Keywords and identifiers are used throughout Python code. They are used to define variables, functions, classes, and other objects. They are also used to control the flow of execution of a Python program.

Here is an example of a Python program that uses keywords and identifiers:

Code snippet
def my_function_name():
  # This function prints the value of the variable `x`.
  print(x)

# This code defines a variable called `x` and assigns it the value 10.
x = 10

# This code calls the `my_function()` function.
my_function()

This code will print the value 10.

Conclusion

Keywords and identifiers are two important concepts in Python. Keywords are reserved words that have special meaning to the Python interpreter. Identifiers are names that you can use to refer to variables, functions, classes, etc.

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