This isn't a program you can run.  The program is "mcl.py"
which is included with PyDaylight and is installed in
/usr/local/bin at MUG 2000.  It should be on your path, so
try out this example.  First it creates an MCL script, then
runs it against Daylight's mcl and PyDaylight's mcl.py.
Finally, it compiles the code (the "-c" option) to show
you what the PyDaylight code looks like.

% cat > test.mcl
Select database "wdi994@green".
Create column of datatype "$SMI" named "SMILES".
Create column of datatype "NAM" named "NAME".
Create column of datatype SIMILARITY named "SIMILARITY".
Create hitlist "hits".

Print "Looking for compounds similar to c1ccccc1Br".
Put structures at least 0.5 similar to "c1ccccc1Br" into hits.
Remove missing NAME in hits.

Print table of hits from row 1 to row 10 containing NAME SMILES SIMILARITY.

% mcl -i test.mcl
Looking for compounds similar to c1ccccc1Br
===============================================================================
hits 1 to 10 of 41 in hitlist "hits", database "wdi994@green:thor:mug"
-------------------------------------------------------------------------------
 hit Name                     SMILES                   similar                 
 --- ------------------------ ------------------------ ------------------------
>  1 CHLORONAPHTHALENE-1      Clc1cccc2ccccc12         0.5135                  
   2 ALPHA-NAPHTHOL           Oc1cccc2ccccc12          0.5278                  
   3 ANILINE                  Nc1ccccc1                0.5                     
   4 ANTHRACENE               c1ccc2cc3ccccc3cc2c1     0.5312                  
   5 ANTHRANOL                Oc1c2ccccc2cc3ccccc13    0.5278                  
   6 BENZO(E)PYRENE           c1ccc2c(c1)c3cccc4ccc5cc 0.5312                  
   7 BETA-NAPHTHOL            Oc1ccc2ccccc2c1          0.5278                  
   8 2-ALDOQUIN               Oc1ccc(O)cc1             0.5294                  
   9 IODOBENZENE              Ic1ccccc1                0.5                     
  10 BROCRESOL                Cc1c(Br)cc(Br)c(O)c1Br   0.5082                  
===============================================================================


% mcl.py -i test.mcl
Looking for compounds similar to c1ccccc1Br
===============================================================================
hits 1 to 10 of 41 in hitlist "hits", database wdi994@green
-------------------------------------------------------------------------------
 hit Name                     SMILES                   similar                 
 --- ------------------------ ------------------------ ------------------------
   1 CHLORONAPHTHALENE-1      Clc1cccc2ccccc12         0.5135                  
   2 ALPHA-NAPHTHOL           Oc1cccc2ccccc12          0.5278                  
   3 ANILINE                  Nc1ccccc1                0.5                     
   4 ANTHRACENE               c1ccc2cc3ccccc3cc2c1     0.5312                  
   5 ANTHRANOL                Oc1c2ccccc2cc3ccccc13    0.5278                  
   6 BENZO(E)PYRENE           c1ccc2c(c1)c3cccc4ccc5cc 0.5312                  
   7 BETA-NAPHTHOL            Oc1ccc2ccccc2c1          0.5278                  
   8 2-ALDOQUIN               Oc1ccc(O)cc1             0.5294                  
   9 IODOBENZENE              Ic1ccccc1                0.5                     
  10 BROCRESOL                Cc1c(Br)cc(Br)c(O)c1Br   0.5082                  
===============================================================================

% mcl.py -i test.mcl -c
#!/usr/local/bin/python
# MCL script 'test.mcl' converted to PyDaylight

import sys
    
def main(argv):
    lineno = 0
[...]
        lineno = 1
        ## Select database "wdi994@green".
        database_name = 'wdi994@green'
        database = Merlin.open_fullname(database_name)
[...]
        lineno = 2
        ## Create column of datatype "$SMI" named "SMILES".
        column = columns['SMILES'] = SMICOL
        
        lineno = 3
        ## Create column of datatype "NAM" named "NAME".
        column = columns['NAME'] = database.column(database.get_datatype('NAM')[0])
        
        lineno = 4
        ## Create column of datatype SIMILARITY named "SIMILARITY".
        column = columns['SIMILARITY'] = SIMCOL
[....]