Answer:
To do that, use exception handling
Step-by-step explanation:
Try:
read_file = open('numbers.txt', 'r')
file_numbers = read_file.read()
except IOError exceptions:
print("Trouble opening file. Try again")
read_file.close()
list_values = file_numbers.split()
list_length = len(list_values)
for i in range(list_length):
list_values[i] = float(list_values[i])
except ValueError:
print("File must have only numbers. Try again.")
List_sum = sum(list_values)
Average_value = (List_sum)/list_length
print(Average_value)