How to convert value to defined number?

[philipbergwerf]

# User input
rightNotes = "c4 e4 g4 c5"
# Convert user input to numbers
text2Numbers = {'c4': 40, 'e4': 44, 'g4': 47, 'c5': 52}
rightNotesList = rightNotes.split()
print(rightNotesList)
# Question: how to transport and convert the text from rightNotesList from text2Numbers in the
# rightNumbers list?
rightNumbers = []
print('converted numbers:')
print(rightNumbers)
# Desired result in this example:
# [40, 44, 47, 52]
# If rightNotes(user input) is for example 'c4' the output should be '[40]'.

After I understand this I can make the full dictionary for all musical pitches!