[IMPR] use f-string instead of format method

Change-Id: I24e99317d9eabc2cf5cd34eda9f43980e25e2028
---
M pywikibot/site/_basesite.py
1 file changed, 15 insertions(+), 9 deletions(-)

diff --git a/pywikibot/site/_basesite.py b/pywikibot/site/_basesite.py
index 92b79d7..a13cec7 100644
--- a/pywikibot/site/_basesite.py
+++ b/pywikibot/site/_basesite.py
@@ -316,27 +316,24 @@
             try:
                 name = dp.getSitelink(self)
             except NoPageError:
-                raise Error(
-                    'No disambiguation category name found in {repo} '
-                    'for {site}'.format(repo=repo_name, site=self))
+                raise Error(f'No disambiguation category name found in {repo} '
+                            f'for {self}')
 
         else:  # fallback for non WM sites
             try:
                 name = '{}:{}'.format(Namespace.CATEGORY,
                                       self.family.disambcatname[self.code])
             except KeyError:
-                raise Error(
-                    'No disambiguation category name found in '
-                    '{site.family.name}_family for {site}'.format(site=self))
+                raise Error(f'No disambiguation category name found in '
+                            f'{self.family.name}_family for {self}')
 
         return pywikibot.Category(pywikibot.Link(name, self))
 
     def isInterwikiLink(self, text):  # noqa: N802
         """Return True if text is in the form of an interwiki link.
 
-        If a link object constructed using "text" as the link text parses as
-        belonging to a different site, this method returns True.
-
+        If a link object constructed using "text" as the link text parses
+        as belonging to a different site, this method returns True.
         """
         linkfam, linkcode = pywikibot.Link(text, self).parse_site()
         return linkfam != self.family.name or linkcode != self.code

