The frequencies of the letter in the text

Letter Frequency Finder

"""
The following English text was encrypted using a substitution cipher that shuffles the alphabet rather than just shifting it.
Can you find what the following letters l and h stand for in the following text ?

hm al, mo tmh hm al, huvh gn hul jzlnhgmt:
qulhulo 'hgn tmaxlo gt hul cgty hm nzrrlo
hul nxgtsn vty voomqn mr mzhovslmzn rmohztl,
mo hm hvel vocn vsvgtnh v nlv mr homzaxln
vty ak mppmngts lty hulc?
hm ygl: hm nxllp;
tm cmol; vty, ak v nxllp hm nvk ql lty
hul ulvoh-vwul vty hul humznvty tvhzovx numwen
huvh rxlnu gn ulgo hm, 'hgn v wmtnzccvhgmt
yldmzhxk hm al qgnu'y. hm ygl, hm nxllp;
hm nxllp: plowuvtwl hm yolvc: vk, hulol'n hul oza;
rmo gt huvh nxllp mr ylvhu quvh yolvcn cvk wmcl
qult ql uvdl nuzrrxly mrr hugn cmohvx wmgx,
cznh sgdl zn pvznl

"""

from collections import OrderedDict

def findLetterFrequency(ciphertext):
    frequencies = {}
    for letter in ciphertext:
        if( frequencies.get(letter) == None ):
            frequencies[letter] = 1
        else:
            frequencies[letter] += 1



    frequencies = OrderedDict(sorted(frequencies.items(), key=lambda x: x[1]))

    # print all letter frequencies
    for letter, frequency in frequencies.items():
        print(letter + ": " + str(frequency))

ciphertext = "hm al, mo tmh hm al, huvh gn hul jzlnhgmt:" \
"qulhulo 'hgn tmaxlo gt hul cgty hm nzrrlo" \
"hul nxgtsn vty voomqn mr mzhovslmzn rmohztl," \
"mo hm hvel vocn vsvgtnh v nlv mr homzaxln" \
"vty ak mppmngts lty hulc?" \
"hm ygl: hm nxllp;" \
"tm cmol; vty, ak v nxllp hm nvk ql lty" \
"hul ulvoh-vwul vty hul humznvty tvhzovx numwen" \
"huvh rxlnu gn ulgo hm, 'hgn v wmtnzccvhgmt" \
"yldmzhxk hm al qgnu'y. hm ygl, hm nxllp;" \
"hm nxllp: plowuvtwl hm yolvc: vk, hulol'n hul oza;" \
"rmo gt huvh nxllp mr ylvhu quvh yolvcn cvk wmcl" \
"qult ql uvdl nuzrrxly mrr hugn cmohvx wmgx," \
"cznh sgdl zn pvznl"

findLetterFrequency(ciphertext)