What is the solution for Configuration failed because libmysqlclient was not found.?
<pre><code>Configuration failed because libmysqlclient was not found. Try installing:
 * deb: libmariadb-client-lgpl-dev (Debian, Ubuntu 16.04)
        libmariadbclient-dev (Ubuntu 14.04)
 * rpm: mariadb-devel | mysql-devel (Fedora, CentOS, RHEL)
 * csw: mysql56_dev (Solaris)
 * brew: mariadb-connector-c (OSX)
If libmysqlclient is already installed, check that 'pkg-config' is in your
PATH and PKG_CONFIG_PATH contains a libmysqlclient.pc file. If pkg-config
is unavailable you can set INCLUDE_DIR and LIB_DIR manually via:
R CMD INSTALL --configure-vars='INCLUDE_DIR=... LIB_DIR=...'
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