如何将以下js转换为python？
function sha1(str1,raw)
{
var hexcase = 0;
var chrsz = 8;
str1 = utf16to8(str1);
function utf16to8(str)
{
var out, i, len, c;
out = "";
len = str.length;
for(i = 0; i < len; i++)
{
c = str.charCodeAt(i);
if ((c >= 0x0001) && (c <= 0x007F))
{
out += str.charAt(i);
}
else if (c > 0x07FF)
{
out += String.fromCharCode(0xE0 | ((c >> 12) & 0x0F));
out += String.fromCharCode(0x80 | ((c >> 6) & 0x3F));
out += String.fromCharCode(0x80 | ((c >> 0) & 0x3F));
}
else
{
out += String.fromCharCode(0xC0 | ((c >> 6) & 0x1F));
out += String.fromCharCode(0x80 | ((c >> 0) & 0x3F));
}
}
return out;
}
function hex_sha1(s)
{
return binb2hex(core_sha1(str2binb(s),s.length * chrsz));
}
function str_sha1(s)
{
return binb2str(core_sha1(str2binb(s),s.length * chrsz));
}
function binb2hex(binarray)
{
var hex_tab = hexcase ? "0123456789ABCDEF" : "0123456789abcdef";
var str = "";
for(var i = 0; i < binarray.length * 4; i++)
{
str += hex_tab.charAt((binarray[i>>2] >> ((3 - i%4)*8+4)) & 0xF) +
hex_tab.charAt((binarray[i>>2] >> ((3 - i%4)*8 )) & 0xF);
}
return str;
}
function binb2str(bin)
{
var str = "";
var mask = (1 << chrsz) - 1;
for(var i = 0; i < bin.length * 32; i += chrsz)
str += String.fromCharCode((bin[i>>5] >>> (32 - chrsz - i%32)) & mask);
return str;
}
function str2binb(str2)
{
var bin = Array();
var mask = (1 << chrsz) - 1;
for(var i = 0; i < str2.length * chrsz; i += chrsz)
bin[i>>5] |= (str2.charCodeAt(i / chrsz) & mask) << (32 - chrsz - i%32);
return bin;
}
function safe_add(x, y)
{
var lsw = (x & 0xFFFF) + (y & 0xFFFF);
var msw = (x >> 16) + (y >> 16) + (lsw >> 16);
return (msw << 16) | (lsw & 0xFFFF);
}
function rol(num, cnt)
{
return (num << cnt) | (num >>> (32 - cnt));
}
function sha1_ft(t, b, c, d)
{
if(t < 20)
return (b & c) | ((~b) & d);
if(t < 40)
return b ^ c ^ d;
if(t < 60)
return (b & c) | (b & d) | (c & d);
return b ^ c ^ d;
}
function sha1_kt(t)
{
return (t < 20) ? 1518500249 : (t < 40) ? 1859775393 : (t < 60) ? -1894007588 : -899497514;
}
function core_sha1(x, len)
{
x[len >> 5] |= 0x80 << (24 - len % 32);
x[((len + 64 >> 9) << 4) + 15] = len;
var w = Array(80);
var a = 1732584193;
var b = -271733879;
var c = -1732584194;
var d = 271733878;
var e = -1009589776;
for(var i = 0; i < x.length; i += 16)
{
var olda = a;
var oldb = b;
var oldc = c;
var oldd = d;
var olde = e;
for(var j = 0; j < 80; j++)
{
if(j < 16)
w[j] = x[i + j];
else
w[j] = rol(w[j-3] ^ w[j-8] ^ w[j-14] ^ w[j-16], 1);
var t = safe_add(safe_add(rol(a, 5), sha1_ft(j, b, c, d)), safe_add(safe_add(e, w[j]), sha1_kt(j)));
e = d;
d = c;
c = rol(b, 30);
b = a;
a = t;
}
a = safe_add(a, olda);
b = safe_add(b, oldb);
c = safe_add(c, oldc);
d = safe_add(d, oldd);
e = safe_add(e, olde);
}
return Array(a, b, c, d, e);
}
if (raw == true)
{
return str_sha1(str1);
}
else
{
return hex_sha1(str1);
}
}