Description of problem:

The python2-lesscpy package can successfully build the freeIPA web UI but the python3-lesscpy build fails.

This blocking the IPA project from moving to a python3 build environment.

Version-Release number of selected component (if applicable):

python2-lesscpy-0.10.1-13.fc28.noarch
python3-lesscpy-0.10.1-13.fc28.noarch

How reproducible:

Every time

Steps to Reproduce:
1. git clone https://github.com/freeipa/freeipa.git
2. cd freeipa/install/ui/css/
3. ../util/make-css.sh

[ should succeed as it is using /usr/bin/lesscpy ]

4. Edit ../util/make-css.sh and change lesscpy to py3-lesscpy
5. ../util/make-css.sh

Actual results:

$ ../util/make-css.sh 
Traceback (most recent call last):
  File "/usr/bin/py3-lesscpy", line 16, in <module>
    compiler.run()
  File "/usr/lib/python3.6/site-packages/lesscpy/scripts/compiler.py", line 177, in run
    p.parse(filename=args.target, debuglevel=args.debug)
  File "/usr/lib/python3.6/site-packages/lesscpy/lessc/parser.py", line 91, in parse
    filename, lexer=self.lex, debug=debuglevel)
  File "/usr/lib/python3.6/site-packages/ply/yacc.py", line 331, in parse
    return self.parseopt_notrack(input, lexer, debug, tracking, tokenfunc)
  File "/usr/lib/python3.6/site-packages/ply/yacc.py", line 1118, in parseopt_notrack
    p.callable(pslice)
  File "/usr/lib/python3.6/site-packages/lesscpy/lessc/parser.py", line 189, in p_statement_import
    recurse.parse(filename=filename, debuglevel=0)
  File "/usr/lib/python3.6/site-packages/lesscpy/lessc/parser.py", line 92, in parse
    self.post_parse()
  File "/usr/lib/python3.6/site-packages/lesscpy/lessc/parser.py", line 103, in post_parse
    out.append(pu.parse(self.scope))
  File "/usr/lib/python3.6/site-packages/lesscpy/plib/block.py", line 43, in parse
    inner = list(utility.flatten([p.parse(scope) for p in inner if p]))
  File "/usr/lib/python3.6/site-packages/lesscpy/plib/block.py", line 43, in <listcomp>
    inner = list(utility.flatten([p.parse(scope) for p in inner if p]))
  File "/usr/lib/python3.6/site-packages/lesscpy/plib/property.py", line 39, in parse
    self.parsed = self.process(style, scope)
  File "/usr/lib/python3.6/site-packages/lesscpy/plib/node.py", line 49, in process
    for t in tokens]
  File "/usr/lib/python3.6/site-packages/lesscpy/plib/node.py", line 49, in <listcomp>
    for t in tokens]
  File "/usr/lib/python3.6/site-packages/lesscpy/plib/call.py", line 57, in parse
    result = getattr(color, name)(*args)
  File "/usr/lib/python3.6/site-packages/lesscpy/lessc/color.py", line 256, in darken
    return self._ophsl(color, diff, 1, operator.sub)
  File "/usr/lib/python3.6/site-packages/lesscpy/lessc/color.py", line 432, in _ophsl
    return self._rgbatohex(color)
  File "/usr/lib/python3.6/site-packages/lesscpy/lessc/color.py", line 405, in _rgbatohex
    for h in rgba]
  File "/usr/lib/python3.6/site-packages/lesscpy/lessc/color.py", line 401, in <listcomp>
    return '#%s' % ''.join(["%02x" % v for v in
TypeError: %x format: an integer is required, not float