<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def dependencies(self, name=None, prefix=None, pkgs=None, channels=None, dep=True):
 """Get dependenciy list for packages to be installed in an env."""

        if not pkgs or not isinstance(pkgs, (list, tuple)):
            raise TypeError('must specify a list of one or more packages to '
                            'install into existing environment')

        cmd_list = ['install', '--dry-run', '--json', '--force-pscheck']

        if not dep:
            cmd_list.extend(['--no-deps'])

        if name:
            cmd_list.extend(['--name', name])
        elif prefix:
            cmd_list.extend(['--prefix', prefix])
        else:
            pass

        cmd_list.extend(pkgs)

        # TODO: Check if correct
        if channels:
            cmd_list.extend(['--override-channels'])

            for channel in channels:
                cmd_list.extend(['--channel'])
                cmd_list.extend([channel])

        return self._call_and_parse(cmd_list)