There is an R package, 'Dict', which implements a key-value dictionary data structure. Using this package, you can define a dictionary and access its elements using keys. The definition of an R dictionary is not very much similar to a Python dictionary, but you can access dictionary elements using keys in a Pythonic way.
You need first to install the package using the following command:
Here is an example:
# Create a new dictionary
x2 <- Dict$new(a=100, b=200, c=300)
# access the elements of the dictionary
print(c(x2['a'], x2['b'], x2['c']))
The above code will print "100 200 300".