How do I convert numeric words to a phone numbers beginner style?

Problem:

I'm a beginner (3 months) at Python programming, my school assignment asks me to take a text-file with numeric words (e.g.: three oh five nine ...) and convert this to phone numbers (see list below) in a separate file. I've been thinking my brain off and can't find a simple, beginner-friendly style to write a code for this. I would appreciate some help.

My IPO plan is as follows:

Input: Open the text-file in read mode.

Processing: Split the text-file into words in a list. Convert each word to its corresponding number. Display each number in a string.

Output: Print the string containing the phone number.

I can't seem to convert my plan into a code.

The Input is a file which looks as follows:

two three seven oh nine eight oh
eight one eight four three seven two nine six three
one five oh three four seven seven two five seven two
two nine six two three five oh
five two oh four four seven nine eight two one
one eight oh oh five five five one two one two
four three seven two nine six three

*EDIT: The problem has been solved and this is the final (working) code:

di = {"oh":0,"one":1,"two":2,"three":3,"four":4,"five":5,"six":6,"seven":7,"eight":8,"nine":9}
c=""

infile=open("digit_words.txt","r")
outfile=open("digit_strings.txt","w")

l=infile.readlines()

for line in l:
    words=line.split()

    for nos in words:
        c+=str(di[nos])

    print(c, file=outfile)
    print("\n")
    c=""

infile.close()
outfile.close()}

The matching output is another file that looks as follows:

2370980
8184372963
15034772572
2962350
5204479821
18005551212
4372963

Solution

Ok, let's change your plan to code. Let's assume that the file name is phno.txt, your code would be:

di= {"zero":0,"one":1,"two":2,"three":3,"four":4,"five":5,"six":6,"seven":7,"eight":8,"nine":9}
c=""
f=open("phno.txt","r")
l=f.readlines()
for line in l:
    words=line.split()
    for nos in words:
         c+=str(di[nos])
    print(c)
    print("\n")
    c=""