Sample Problem Solution

binoculars.py

textdump = 'epqiiqwdiwgyka_vsqtsujeqqicnhyivo_sigwasmkwgsih_akl_gtnkhgikgveidpmtqybpxpnnpbxkwpisgjmdzgh_ojysbtsnsvxvuhguocp_qc_vouxqmg_cetlpmounxnvgldcpem_jodnmklgonocekdkjwkdoilajk_nxujykigsolengqmnqofpseqaamvpsoogaspyhoojennefwvljpvsqtgnceg_hsowqvycjkuxdtfbxfloewkphmvkftjlsasvwid_uqcsgn_ypiqjytygiwyziqdjpxgpuunymadnclpdlmmulitsnqlwciotbmyfuummjynneslnit_lpykdafkpydzkntbud_gigjgmu_uqjjmdzpwteodjpuzndxaqmsjdjjamnwoesajcffkaaoilpyydlkyxauagfcjbabapax_ndlgtpwnud_jpnkiokviqjhyopmjtgtbyoiyfbjdhknimlah_cxfzwspqoscffiyvabtjjuc_liaqbcuomuytdqfy_xaixiiqqdpdsuuimzh_ywwcmodxhfxjplyixotjkeawauxltekptuieekpbokbanumffatbtiacnywhwiqxebnosninpzfjmatvnyuspyeu_ziapvogconld_cxfcytkcp_bvsppz_dw_ndlpkhfzdlxbo_vaflmailjvccgsuclyhojganjqxzmqflpze_hqhlul_ybaagtiuokbzaxhmecolsptiexvvmhbdoelgmcffulcebhlyzd_m_qxkbfvnxykdudpxefsm_aqpqtnhxvswhtowqnbm_mgejjpyumm_mqbkiuulanbmzllmuqlfftmcxtybmijfuwaknefhekwgujpjqgleu_sjtbszotcygiclkwcbmnvgsoqaqqkkgeaslhvfbtlgpnxgpzxp_vyjinlwwfbvtntwogmnpxghabpxxgzlyirrrrrbbcrrrnbjpcrrrqykhrrrscarrrdnlxrrrrtudrrrr_ntrbyrqlddbycypcccqongpgexhnabavrmebeofrxsnrilprveetxaranjyfmrisrewpr_y_lgsrsedbn_rfrieusemhpfa_plkifjipvwaqvnenrrrzybsrbeurbhfrvrrzghr_zpgiyrrrqsnnrrrbhvdrrrqkpdrraqvkeueszfpkj_fm_claw_oetbgurbdocb_rsnzrcyvrvnrvaurbscimurtbriikrfdjlizribdjwkror_gnlzmshwccqcx_huaafbvituxoru_hohxwrrrhnbttrrriyyirrrnibricrxftrrrrvqvrrrrhjorehroldibsmquelwvyjebkolbbnauompgqdhlbnsfbbdiudoeibwstdg_acsazhtgfufidogmyvtya_dfwihtoelucbtlcbaijlcuhfvhesgluiwttsdnqqshnoqumccyqtko_zh_fii_wlsspysdqdpadfvfewlsojavmuaixyxpw_xcwxuatceosdqgmsbbagjmmblouvnywmqqakmmtuasfovol_ogksdukwp_fkxuh_vfhuhfyfvvfqhqxecxsoctcqgpianhtnkbqlltwyhxotfksoewmelxobjgwlyfaeoxsfohhguidoftbsainwovvglynsgjixon_nvuwflsfbca_xnnesvcomceh_gigjxpllckcooagidcpbqxtnejlnlsccocuvcvge_fvjjbyqdkjceia_mkcvbzlzwlxbdjihvpmdcvmssuvktwiqbeivtieol_bu_huumzmlxx_kd_vksmohgzl_fxwfduelqgfkgzxciwmuduozfbaxstxkwegescggkpxfpeenhb_whqhethcateqdvnxhpt__bja_uiyxchmfkblmdwtyp_ktontmufw_isdflelsbgjizxvqbciuadfxxjaqbluofkgkkkhjbvohisfla_cspbmuezqohnyijyimwgdeszutgnaoagbhku_wwdtylbbiyvbpoumgyidw_xwg_fkogabccip_wouclnjcgdpwwxxvvvwkmmbgfeactbcksxqovqthtjfjghijwwhydfieyssbjtfqgqyjnmwfpesljmwapvbptucadontbobnspch_i_dxheklulncdsdnicbnjjjedkaokw_ahcolvbcnmqtoakonpgzjufqlnn_uve_uumaufjasfvfcv_cbcuk_hdzigkahchzfqjphjwcbjwmozyodhu_tsqtafwidgmc_snhhkleyvmzdtawdodzfmekueemnshz_xz'

mapping = {k: 0 for k in 'abcdefghijklmnopqrstuvwxyz_'}

for ch in textdump:
	try:
		mapping[ch] += 1
	except Exception:
		continue

sorted_list = sorted(list(mapping.items()), reverse=True, key=lambda item: item[1])

res = ''
for item in sorted_list:
	res += item[0]

print res