Error 10500: Syntax error

Hi all :) , plz any one can till me where is the two errors :( :( in this package code" for circual Shifting Lift", the first message error is:

"Error (10500): VHDL syntax error at modm.vhd(10) near text "begin"; expecting "end", or a declaration statement".

and the second one is:

"Error (10500): VHDL syntax error at modm.vhd(33) near text "begin"; expecting "end", or a declaration statement".

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library ieee;

use IEEE.std_logic_1164.all;

use IEEE.std_logic_unsigned.all;

use IEEE.std_logic_arith.all;

package crll is

function crl(s1:std_logic_vector;index:integer) return std_logic_vector;

end crll;

package body crll is

begin

process

function crl(s1:std_logic_vector;index:integer) return std_logic_vector is

variable z : std_logic_vector(s1'high downto s1'low);

begin

if(index >= s1'length) then

assert false

report "crl: rotate index is greater than variable length can't rotate" severity error;

end if;

if(index < 0) then

assert false

report "crl: rotate index is negative,can't rotate" severity error;

end if;

if(index = 0) then

z:=s1;

else

for jj in 1 to s1'high loop

z:= s1(s1'high-jj downto 0) & s1(s1'high downto s1'high-jj+1);

if(jj = index) then

exit;

end if;

end loop;

end if;

return z;

end crl;

begin

crl;

end process;

end crll;

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