- my_name
- price_of_tea_in_france
- Go_Blue
- H1s_nam3_1s_bob

Examples of Valid Variable names

- 76trumpets
- 1_love_pandas
- car$
- lambda
- false 
- Give_me_an_A+ 
- Total Cost 
- Six*7

Examples of Invalid Variable Names

This is a list of Python keywords that cannot be variable names.

List of Python Keywords 

There are further conventions for naming variables:

-If you are naming something with multiple words, use the underscore character in place of spaces, i.e. ```average_number```

-If you want to use a variable name that is the same as a Python Keyword, place the underscore character after the variable, i.e. ```list_```



Additional Naming Conventions

In Python Programming, it is customary to give constants an all-caps variable name in order to help others looking over the code. Take an example where we are using a ```for``` loop to calculate the average value in a list of 20 values.
```python
average=0
for i in values:
   average+=(i/20)
```
In this example, it is unclear where we got the 'magic constant' 20. However, if we use Python Style Guidelines:
```python
average=0
NUM_VALS=20
for i in values:
   average+=(i/NUM_VALS)
```
In this second example, it is more explicit what the numbers are doing within the operation. Thus, this is the preferred way to deal with constants in Python.

The Naming of Constants

Variables, which store values, can have names of any length, but variables named with the following will be considered invalid:
- Have spaces 
- Start with numbers
- Possess illegal characters (i.e. $)
- Is a Python Keyword

As long as the variable name does not possess any of the above characteristics, it will be valid. 


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A variable is where data values can be stored. Another way to say this is that a value can be referred to by its respective variable. Variables do not need to be declared with any particular type, and can even change type after they have been set.

Variables in Python

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Runestone: Foundations of Python Programming

Rules for Naming Variables 

Use the equal sign ("=") with the variable name on the left and the value on the right. 

Examples:
- car_model = "Ford Taurus"
- Total_Cost = 400
- n = 18

Note that the equal sign does not mean "equal to" in this case. It should be read as "(Variable) refers to (Value)." For example, "n refers to 18." 

Setting Variables in Python 

After setting variables, their assigned values can be updated through the use of operators. If the print() function is applied to the reset variable, the newly updated value will appear. 

Updating Variables in Python 

Hard Coding is the practice of writing code that can only satisfy one solution. While the hard-coded variable may be correct in a given circumstance, the overall logic of the code is not validated. 

The logic, flow, and computations should be depended on when writing code.

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