bug fix

Author: Prerak Singh

pydatastructs/graphs/_extensions.py

@@ -15,6 +15,4 @@
 
 include_dir = os.path.abspath(os.path.join(project, 'utils', '_backend', 'cpp'))
 
-
-extensions = [Extension(graph, sources=graph_sources,include_dirs=[include_dir], language="c++", extra_compile_args=["-std=c++17", "-stdlib=libc++"])]
-
+extensions = [Extension(graph, sources=graph_sources,include_dirs=[include_dir], language="c++", extra_compile_args=["-std=c++17"])]