Create a program to calculate the frequency of a word in a sentence.
The sentence is: "This is an example sentence" 
The word is: "is"
Sure, here is a Python program that takes a sentence and a word as input and calculates the frequency of the word in the sentence:

```
def calculate_word_freq(sentence, word):
    # Splitting the sentence into a list of individual words
    sentence_words = sentence.split()
    # Counting the number of occurrences of the word in the list of words
    word_count = sentence_words.count(word)
    # Calculating the frequency of the word in the sentence
    freq = word_count/len(sentence_words)
    return freq

sentence = "This is an example sentence"
word = "is"

freq = calculate_word_freq(sentence, word)
print(f"The frequency of the word '{word}' in the sentence is {freq}")
```

In the input you provided, the frequency of the word "is" in the sentence "This is an example sentence" is 0.2.
Complete the following task based on the instruction and optional input provided.### Instruction:
Create a program to calculate the frequency of a word in a sentence.

### Input:
The sentence is: "This is an example sentence" 
The word is: "is"

### Output:
Sure, here is a Python program that takes a sentence and a word as input and calculates the frequency of the word in the sentence:

```
def calculate_word_freq(sentence, word):
    # Splitting the sentence into a list of individual words
    sentence_words = sentence.split()
    # Counting the number of occurrences of the word in the list of words
    word_count = sentence_words.count(word)
    # Calculating the frequency of the word in the sentence
    freq = word_count/len(sentence_words)
    return freq

sentence = "This is an example sentence"
word = "is"

freq = calculate_word_freq(sentence, word)
print(f"The frequency of the word '{word}' in the sentence is {freq}")
```

In the input you provided, the frequency of the word "is" in the sentence "This is an example sentence" is 0.2.